Nemawar is notable for the Siddhanatha temple, also known as the Siddeshwar Mahadeva temple. This temple is significant for the following reasons:

• One of India's best preserved pre-13th century Bhumija-architecture temples
• India's best preserved Paramara-era Hindu temple
• One of central India's best preserved 10th-century Hindu temples
• 99 niches and panels of elegantly sculpted Hindu artwork (lower bands are damaged, upper band is better preserved)
• Scholars have called this temple "magnificent" and "among the finest".

The Siddhanatha temple faces south, has a sabhamandapa, an antarala and a garbhagriya. Its shikhara (spire) towers over the sanctum with symmetric order of miniature shikharas. The sabhamandapa consists of a gudhamandapa with three mukhamandapa for entrance from three cardinal directions. The outer walls of the temple have artwork of Shaiva, Vaishnava, Shakta and Saura traditions, as well as many Vedic deities. The panels also include cultural scenes of artha, kama (amorous couples, mithuna), dance, music and festivals. Inside the sanctum is a Shiva linga on an arghyapatta.

The temple is made in two stones – yellowish sandstone and bluish-pink sandstone, likely because its expansion was completed with the second type of stone. The temple has two important inscriptions, both by visiting pilgrims. The older inscription is from the 12th century and is on the second type of stone. The architectural features and iconography suggests that this temple was completed in late 10th-century. Some scholars date it to the first half of the 11th-century.