Semarang (Javanese: ꦏꦸꦛꦯꦼꦩꦫꦁ) is the capital and largest city of Central Java province in Indonesia. It was a major port during the Dutch colonial era, and is still an important regional center and port today. The city has been named as the cleanest tourist destination in Southeast Asia by the ASEAN Clean Tourist City Standard (ACTCS) for 2020–2022.

It has an area of 373.78 km (144.32 sq mi) and had a population of 1,555,984 at the 2010 census and 1,653,524 at the 2020 census, making it Indonesia's ninth most populous city after Jakarta, Surabaya, Bekasi, Bandung, Medan, Depok, Tangerang and Palembang; the official population estimate as at mid-2023 was 1,694,740, comprising 838,440 males and 856,310 females. The built-up urban area had 3,183,516 inhabitants at the 2010 census spread over two cities and 26 districts. The Semarang metropolitan area (a.k.a. Kedungsepur) has a population of over 6 million in 2020 (see Greater Semarang section). The population of the city is predominantly Javanese with significant Chinese presence.

The history of Semarang goes back to the 9th century, when it was known as Bergota. At the end of the 15th century, appointed by the demak sultanate an islamic scholar named Ki Ageng Pandan Arang [id] founded a village and an Islamic school in this fishing village. On 2 May 1547, Sultan Hadiwijaya of Pajang declared Pandan Arang as the first bupati (mayor) of Semarang, thus creating Semarang administratively and politically.

In 1678, Sunan Amangkurat II promised to give control of Semarang to the Dutch East India Company (VOC) as a part of a debt payment. In 1682, the Semarang state was founded by the Dutch colonial power. On 5 October 1705 after years of occupations, Semarang officially became a VOC city when Susuhunan Pakubuwono I made a deal to give extensive trade rights to the VOC in exchange of wiping out Mataram's debt. The VOC, and later, the Dutch East Indies government, established tobacco plantations in the region and built roads and railroads, making Semarang an important colonial trading centre.

The historic presence of a large Indo (Eurasian) community in the area of Semarang is also reflected by the fact a creole mix language called Javindo existed there.

Semarang was handed by the Sultan of Mataram to the Dutch East Indies in 1678. The city was pictured as a small settlement with a pious Muslim area called Kauman, a Chinese quarter, and a Dutch fortress. The fortress has a pentagonal form with only one gate in the south and five monitoring towers to protect the Dutch settlement from rebellion actions, segregating the spaces between Dutch settlement and other areas. In fact, the city of Semarang was only referred to the Dutch quarter while the other ethnic settlement were considered as villages outside the city boundary. The city, known as de Europeesche Buurt, was built in classical European style with church located in the centre, wide boulevards, streets and villas. According to Purwanto (2005), the urban and architectural form of this settlement is very similar to the design principles applied in many Dutch cities.

Due to the long and costly Java War, there was not much funding from the Dutch East Indies government, and this affected Semarang's development. Most land in the area was used for rice cultivation and the only small improvement was the development of a surrounding fortress. Although less developed, Semarang is a fairly well organized city, in which urban activities were concentrated along the river and the settlement is linked to a market where different ethnic groups met to trade. The existence of the market, in the later years, become a primary element and a generator of urban economic growth.

After the departure of Herman Willem Daendels, Napoleonic governor of Java, the Dutch reorganized Java into Residencies, and Semarang became the seat of the new Semarang Residency in 1817. An important influence on urban growth was the Great Mail Road project in the 1847, which connected all the cities in the northern coast of Central and East Java and positioned Semarang as the trade centre of agricultural production. The project was soon followed by the development of the Staatsspoorwegen Railway and the connecting roads into the inner city of Semarang at the end of the 19th century. Colombijn (2002) marked the development as the shift of urban functions, from the former river orientation to all services facing the roads.

The Dutch East Indies' mail and railway projects improved communication and transportation, bringing an economic boom to the city in the 1870s. Hospitals, churches, hotels, and mansions were built along the new main roads of Mataram Street, Bojongscheweg, and Pontjolscheweg. The Javanese quarters of town known as kampongs grew increasingly densely populated, reaching as many as 1000 inhabitants per hectare and degrading living conditions. Mortality remained high into the early 20th century, with newcomers, overcrowding, and poor hygiene triggering cholera and tuberculous outbreaks. Dysentery, typhoid, and malaria were also rife. The city doctor Willem T. de Vogel advocated strenuously for reducing overcrowding and improving living conditions by extending Semarang into the less malarial hill country to its south; his fellow councilman Hendrik Tillema had campaigned on a platform of combatting malaria and joined De Vogel's scheme, broadening it into a "village improvement" (Dutch: kampongverbetering) movement. Purchasing land in the heights with their own money, the two men and some friends passed it on to the city with an initial zoning plan by KPC de Bazel in 1907 but could never convince a majority of the council to support its development. Changing tack, Tillema then worked to improve the existing kampongs in the city's malarial districts by improving drainage and providing more sanitary public toilets and public housing.

A decade later, the town approved Thomas Karsten's revised plan for the area, using it to build larger villas for the Dutch and wealthy Chinese and Javanese rather than allowing its use by the poor. This area became known as Candi Baru (Dutch: Nieuw Tjandi) and forms the core of the present-day Candisari District. Although it remained highly stratified by class, Candi Baru had less ethnic segregation than the older area of town and incorporated public squares, athletic facilities, and places for public bathing and washing that could be used communally. With most work remaining in the lower city and transportation slow or expensive, few of the lower classes were interested in moving to the district but it set a pattern that was followed with three more successful housing plans between 1916 and 1919. The population grew by 55%, adding 45,000 Javanese, 8500 Chinese, and 7000 Europeans. Karsten's approach to town planning emphasized its aesthetic, practical, and social requirements articulated in economic terms rather than purely racial ones.

Driven by economic growth and spatial city planning, the city had doubled in size and expanded to the south by the 1920s, creating a nucleus of a metropolis where multi-ethnic groups lived and traded in the city. The villages in the suburbs such as Jomblang and Jatingaleh steadily became the satellite towns of Semarang, more populated with a bigger market area. Before the invasion of Japan in 1942, Semarang had already become the capital of Central Java province, as the result of trade and industrial success and spatial planning.

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  NIS company head office (Gedung Lawang Sewu), Semarang, Dutch East Indies.
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  A Chinese house in Semarang at the turn of the 20th century.
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  Aerial picture of Old Semarang area in the 1920s.
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  Old 0-6-0 locomotive next to the Lawang Sewu building.

The Japanese military occupied the city, along with the rest of Java, in 1942, during the Pacific War of World War II. During that time, Semarang was headed by a military governor called a Shiko, and two vice governors known as Fuku Shiko. One of the vice governors was appointed from Japan, and the other was "chosen" from the local population.

After Indonesian independence in 1945, Semarang became the capital of Central Java on 18 August 1945, headed by Mr. Moch.Ichsan.

It also became the site of a battle (Five days battle, Pertempuran lima hari) between the new Indonesian military and Japanese soldiers in October 1945. Shortly after that, what had been the Indonesia-conducted Ambarawa, Magelang, and Ungaran offensives reached Semarang city on 15 December 1945, causing an 87-day battle that swept away the British and Dutch military completely.

Semarang city administration is headed by mayor, with a legislative assembly. Both mayor and the 50 members of legislative assembly are elected by direct vote. The government of Semarang City had implemented the smart city concept since 2013.

Juridically, Semarang City is a municipality (second level area) consisting of 16 districts (kecamatan), which are again divided into 177 urban villages (kelurahan). The districts are tabulated below with their areas and their populations at the 2010 census and 2020 census, together with the official estimates as at mid 2023. The table also includes the number and names of the urban administrative villages in each district.

Kode Wilayah	District (kecamatan)	Area in km	Pop'n census 2010	Pop'n census 2020	Pop'n estimate mid 2023	No. of villages	Administrative villages (kelurahan)
33.74.14	Mijen (Javanese: ꦩꦶꦗꦺꦤ꧀, romanized: Mijèn)	56.52	55,708	80,906	89,950	14	Cangkiran, Bubakan, Jatibarang, Jatisari, Karangmalang, Kedungpane, Mijen, Ngadirgo, Pesantren, Polaman, Purwosari, Tambangan, Wonolopo, Wonoplumbon,
33.74.12	Gunungpati (Javanese: ꦒꦸꦤꦸꦁ​ꦥꦛꦶ, romanized: Gunungpathi)	58.27	88,444	98,023	100,750	16	Cepoko, Gunungpati, Jatirejo, Kalisegoro, Kandri, Mangunsari, Ngijo, Nongkosawit, Pakintelan, Patemon, Plalangan, Pongangan, Sadeng, Sekaran, Sukorejo, Sumurejo
33.74.11	Banyumanik (Javanese: ꦧꦚꦸꦩꦤꦶꦏ꧀, romanized: Banyumanik)	29.74	136,368	142,076	143,430	11	Pudakpayung, Gedawang, Jabungan, Padangsari, Banyumanik, Srondol Wetan, Pedalangan, Sumurboto, Srondol Kulon, Tinjomoyo, Ngesrep
33.74.09	Gajah Mungkur (Javanese: ꦒꦗꦃꦩꦸꦁ​ꦏꦸꦂ, romanized: Gajah Mungkur)	9.34	59,911	56,232	56,350	8	Bendanduwur, Bendanngisor, Bendungan, Gajahmungkur, Karangrejo, Lempongsari, Petompon, Sampangan
33.74.07	Semarang Selatan (South Semarang) (Javanese: ꦱꦼꦩꦫꦁ​​ꦏꦶꦢꦸꦭ꧀, romanized: Sěmarang Kidul	5.95	69,617	62,030	62,180	10	Barusari, Bulustalan, Lamper Kidul, Lamper Lor, Lamper Tengah, Mugassari, Peterongan, Pleburan, Randusari, Wonodri
33.74.08	Candisari (Javanese: ꦕꦤ꧀ꦝꦶꦱꦫꦶ, romanized: Candhisari)	6.40	75,879	75,456	75,610	7	Candi, Jatingaleh, Jomblang, Kaliwiru, Karanganyargunung, Tegalsari, Wonotingal
33.74.10	Tembalang (Javanese: ꦠꦼꦩ꧀ꦧꦭꦁ, romanized: Tĕmbalang)	39.47	159,849	189,680	198,860	12	Bulusan, Jangli, Kedungmundu, Kramas, Mangunharjo, Meteseh, Rowosari, Sambiroto, Sendangguwo, Sendangmulyo, Tandang, Tembalang
33.74.06	Pedurungan (Javanese: ꦥꦼꦢꦸꦫꦸꦔꦤ꧀, romanized: Pědurungan)	21.11	180,468	193,151	196,530	12	Gemah, Kalicari, Muktiharjo Kidul, Palebon, Pedurungan Kidul, Pedurungan Lor, Pedurungan Tengah, Penggaron Kidul, Plamongan Sari, Tlogomulyo, Tlogosari Kulon, Tlogosari Wetan,
33.74.05	Genuk (Javanese: ꦒꦼꦤꦸꦏ꧀, romanized: Genuk)	25.98	92,314	123,310	132,470	13	Bangetayu Kulon, Bangetayu Wetan, Banjardowo, Gebangsari, Genuksari, Karangroto, Kudu, Muktiharjo Lor, Penggaron Lor, Sembungharjo, Terboyo Kulon, Terboyo Wetan, Trimulyo
33.74.04	Gayamsari (Javanese: ꦒꦪꦩ꧀ꦱꦫꦶ, romanized: Gayamsari)	6.22	71,767	70,261	70,410	7	Gayamsari, Kaligawe, Pandean Lamper, Sambirejo, Sawah Besar, Siwalan, Tambakrejo
33.74.03	Semarang Timur (East Semarang) (Javanese: ꦱꦼꦩꦫꦁ​​ꦮꦺꦠꦤ꧀, romanized: Sěmarang Wétan)	5.42	74,782	66,302	66,480	10	Bugangan, Karangtempel, Karangturi, Kebonagung, Kemijen, Mlatibaru, Mlatiharjo, Rejomulyo, Rejosari, Sarirejo, Bandarharjo
33.74.02	Semarang Utara (North Semarang) (Javanese: ꦱꦼꦩꦫꦁ​​ꦭꦺꦴꦂ, romanized: Sěmarang Lor)	11.39	117,836	117,605	117,890	9	Bulu Lor, Dadapsari, Kuningan, Panggung Kidul, Panggung Lor, Plombokan, Purwosari, Tanjungmas
33.74.01	Semarang Tengah (Central Semarang) (Javanese: ꦱꦼꦩꦫꦁ​​ꦩꦢꦾ, romanized: Sěmarang Madyå)	5.17	60,312	55,064	55,210	15	Bangunharjo, Brumbungan, Gabahan, Jagalan, Karangkidul, Kauman, Kembangsari, Kranggan, Miroto, Pandansari, Pekunden, Pendrikan Kidul, Pendrikan Lor, Purwodinatan, Sekayu
33.74.13	Semarang Barat (West Semarang) (Javanese: ꦱꦼꦩꦫꦁ​​ꦏꦸꦭꦺꦴꦤ꧀, romanized: Sěmarang Kulon)	21.68	154,878	148,879	149,330	16	Bojongsalaman, Bongsari, Cabean, Gisikdrono, Kalibanteng Kidul, Kalibanteng Kulon, Karangayu, Kembangarum, Krapyak, Krobokan, Manyaran, Ngemplaksimongan, Salamanmloyo, Tambakharjo, Tawangmas, Tawangsari
33.74.16	Tugu (Javanese: ꦠꦸꦒꦸ, romanized: Tugu)	28.13	29,436	32,822	33,800	7	Jerakan, Karanganyar, Mangkang Kulon, Mangkang Wetan, Mangunharjo, Randu Garut, Tugurejo
33.74.15	Ngaliyan (Javanese: ꦔꦭꦶꦪꦤ꧀, romanized: Ngaliyan)	42.99	128,415	141,727	145,500	10	Bambankerep, Beringin, Gondoriyo, Kalipancur, Ngaliyan, Podorejo, Purwoyoso, Tambak Aji, Wonosari

Semarang is located on the northern coast of Java. The city of Semarang is one of the most important cities located on the north coast of Java and is the main hub connecting Jakarta and Surabaya, and cities in the southern interior of Java Surakarta and Yogyakarta. Semarang City has a height ranging from 2 m (6.6 ft) below sea level up to 340 m (1,120 ft) above sea level with a slope of 0%–45%. Semarang City is a city that has a unique topographic condition in the form of a narrow lowland area and hilly areas extending from the west side to the east side of Semarang City. The city is located about 558 km (347 miles) east of Jakarta and 312 km (194 miles) west of Surabaya.

Lowland areas in Semarang City are very narrow. The lowland area in western Semarang only has a width of 4 km (2.5 miles) from the coastline, while in the eastern Semarang, the low-lying area has a width of 11 km (6.8 miles) from the coastline. This lowland area is a flood plain from the large rivers that flow in Semarang City, such as Kali Garang (West Flood Canal), Pengkol River, and Bringin River. This low-lying area stretches on the northern side of Semarang and covers almost 40% of the total area of Semarang. This lowland area is known as the lower town (Semarang Ngisor), as well as the center of the city's economic activity. Under these conditions, the lower city area is often hit by annual flooding and its peak during the rainy season. In a number of regions, especially North Semarang, floods are sometimes also caused by overflowing sea tides (tidal floods). The hilly area in Semarang stretches on the south side. These hills are part of a series of northern Java mountain ranges that stretch from Banten to East Java. The hilly area in the city of Semarang is known as the upper city (Semarang Dhuwur). This hilly region is also the upstream area of the big rivers that flow in the city of Semarang. The upper city area is also near Mount Ungaran.

Semarang features a tropical monsoon climate (Köppen: Am). The city features distinctly wetter and drier months, with June through August being the driest months. However, the average monthly rainfall does not fall below 60 mm (2.4 in), hence the tropical rainforest categorization. Semarang on average sees approximately 2,800 mm (110 in) of rain annually. Average temperatures in the city are relatively consistent, hovering around 28 °C (82 °F). Diurnal temperature variation slightly increases in the dry season.

Like Singapore River, Semarang is constructing Semarang River at Banjir Kanal Barat (Garang River) near Karangayu Bridge. In the middle of July 2011, gardens in river banks and some traditional boats are available to use. The project will be finished in 2013 with river gardens, trotoars, garden lighting, water activities, art sites, sport sites and balconies and stairs for sightseeing. In August 2011, a 421 m (1,380 ft) tunnel dodger at Kreo river has been finished and Jatibarang Dam construction can begin, with completion targeted for July 2013. The dam is planned to release 230 m/s (8,100 cu ft/s) of flood water and will generate 1.5 MW of electricity, provide a drinking water resource and a boost to tourism.

Historical population

Year	Pop.	±%
1950	371,000	—
1955	424,374	+14.4%
1960	485,444	+14.4%
1965	552,128	+13.7%
1970	626,703	+13.5%
1975	782,967	+24.9%
1980	1,009,460	+28.9%
1985	1,125,836	+11.5%
1990	1,242,737	+10.4%
1995	1,333,157	+7.3%
2000	1,427,341	+7.1%
2005	1,438,733	+0.8%
2010	1,555,984	+8.1%
2015	1,698,777	+9.2%
2020	1,653,524	−2.7%
2022	1,659,975	+0.4%
source:

The largest ethnic group in Semarang is the Javanese, followed by minorities of Chinese, Arabs, Indian, and others (including local ethnicities such as Sundanese, Batak, Madura, Malay, Balinese etc.). The dominant religion is Islam with a significant Christian minority.

Semarang has a large Chinese community. As in other regions of Java, especially in Central Java, they have mingled closely with the local population and use Javanese in communication for hundreds of years. About 3.5% of the city's population is ethnic Chinese, many residing in a Chinatown in the vicinity of Gang Pinggir. The Chinatown is called "Kampong Pecinan Semawis" and expresses many aspects of traditional Chinese culture including foods, rituals, and houses of worship.

As the capital city of Central Java, and fifth largest city of Indonesia, the economy of Semarang is quite large. Semarang has transformed and changed dynamically towards a better direction. In a period of less than 10 years, Semarang Metropolitan continues to build a vital financial contribution to Indonesia due to the growing trade and industry and services. As a consequence, people's purchasing power increased, capital inflows, consumer confidence, and doing business indexes were relatively conducive to the development of several CBDs such as Simpang Lima City Center (SLCC), Pemuda Central Business District (PCBD), and Gajahmada Golden Triangle (GGT). Major Indonesian and international financial and banking sectors alikes such as Bank Mandiri, BCA, BNI, BRI, Panin Bank, HSBC, Bank Permata, Standard Chartered, RaboBank, Citibank, DBS, UOB, OCBC NISP, KEB Hana Bank, CIMB Niaga, and Maybank have regional offices in Semarang.

The western part of the city has many industrial parks and factories. Like other metropolitan cities within Indonesia, due to a developing economy and increasing income, Semarang has many shopping malls.

Semarang is on the Indonesian National Route 1 road, which connects it to Merak and Ketapang (Banyuwangi). Indonesian National Route 14 toward Bawen starts here. Semarang has a toll road, the Semarang Toll Road. The city is connected to Solo by Semarang–Solo Toll Road.

Semarang's largest bus terminals are Mangkang and Terboyo. The primary means of public transportation is by minibus, called "bis". Ojek (motorcycle taxis), Angkot (share-taxi) micro-buses, taxi-cabs plays vital role in public transportation of the city. Go-Jek and Grab have online taxi and Ojek services.

Semarang is served by bus rapid transit called Trans Semarang, which operates in six routes. Perum DAMRI also serves in six designated routes in the city.

Semarang was connected to Surakarta (Solo) by a rail line in 1870. At present there are two large train stations in Semarang: Semarang Poncol and Semarang Tawang. Semarang is connected to Bandung, Jakarta, and Surabaya by inter-city train services. Kedungsepur commuter rail connects Semarang Poncol Station eastward to Ngrombo Station in Grobogan Regency.

Semarang's Ahmad Yani International Airport is served by a number of operators including AirAsia, Citilink, Batik Air, Garuda Indonesia, and Lion Air which provide services to Jakarta, Bali, Kuala Lumpur, and Singapore. In 2018, the airport terminal was relocated to a new and much larger site; the old terminal continues to be used for government and military flights.

The main seaport is the Tanjung Mas seaport.