Ainharp (French pronunciation: [ajɲaʁp]; Basque: Ainharbe) is a commune in the Pyrénées-Atlantiques department in the Nouvelle-Aquitaine region in southwestern France.

Ainharp is located some 50 km west by southwest of Pau, 15 km southeast of Saint-Palais, and 10 km north-west of Mauleon-Licharre. It is part of the former province of Soule.

The commune can be accessed by road D242 from Lohitzun-Oyhercq in the west passing through the village and continuing southeast to Mauleon-Licharre. The D344 road also goes to the north from the village through the commune then east to Espes-Undurein. The commune terrain is undulating of mixed farmland and forest.

Located in the drainage basin of the Adour, the commune is the source of numerous streams including the Lagardoye which forms part of the south-eastern border, the Quihilleri which forms much of the western border, and the Lafaure which forms much of the northern border.

The commune name in Basque is Ainharbe.

Jean-Baptiste Orpustan proposed two etymological interpretations:

• a meaning of "low heather" from ilharr meaning "heather" and -be (from behere meaning "low") or
• "height of the low rocks" from gain meaning "high" and har meaning "rock" that indicates the high position of the village on the left bank of the Saison.

The following table details the origins of the commune name and other names in the commune.

Name	Spelling	Date	Source	Page	Origin	Description
Ainharp	Ayharp	1472	Raymond	4	Notaries	Village
	Ainharp	1479	Orpustan	224
	L'Espitau d'Anharp	1479	Raymond	4	Ohix
	Aynharp	1479	Raymond	4	Ohix
	Aignharp	1608	Raymond	4	Insinuations
	Ayharp	1690	Orpustan	224
Carricaburu	Carricaburue	1479	Raymond	42		Farm
Habiague	Habiague	1476	Raymond	74	Ohix	Farm
Lafaure	La Phaura	1538	Raymond	135	Reformation	Stream on the northern border
	La Phaure	1863	Raymond	135
Lambare	lo bedat de Lambarre	1476	Raymond	91	Ohix	Hamlet and Wood
Chemin Mercadieu	lo cami Mercadieu	1479	Raymond	112	Ohix	Farm
	le cami deu Mercat	1479	Raymond	112

Sources:

• Raymond: Topographic Dictionary of the Department of Basses-Pyrenees, 1863, on the page numbers indicated in the table. (in French)
• Orpustan: Jean-Baptiste Orpustan, New Basque Toponymy

Origins:

• Notaries: Notaries of Labastide-Villefranche
• Ohix:Contracts retained by Ohix, Notary of Soule
• Insinuations: Insinuations of the Diocese of Oloron
• Reformation: Reformation of Béarn

Paul Raymond noted on page 4 of his 1863 dictionary that the commune was a former priory in the diocese of Oloron and that there was a hospital for pilgrims.

List of Successive Mayors of Ainharp

Mayors from 1929

From	To	Name
1929	1950	Jean Guiresse
1950	1959	François Elissiry
1959	1971	Jean-Pierre Aguer
1971	1983	Jean Lascaray
1983	2026	Jean-Pierre Arhanchiague

Ainharp is a member of seven intercommunal structures:

• the Communauté d'agglomération du Pays Basque
• the association to support Basque culture
• the intercommunal association of the Valley
• the intercommunal association for the construction and operation of the CES of Mauleon
• the AEP association for Soule Country
• the remediation association for Soule Country
• the energy association of the Pyrénées-Atlantiques

The inhabitants of the commune are known as Ainharbars or Ainharbear.

Historical population

Year	Pop.	±% p.a.
1968	194	—
1975	186	−0.60%
1982	181	−0.39%
1990	161	−1.45%
1999	142	−1.39%
2007	151	+0.77%
2012	143	−1.08%
2017	141	−0.28%
Source: INSEE

The activity is mainly agricultural (maize and livestock). The town is part of the Appellation d'origine contrôlée (AOC) zone of Ossau-iraty.

The commune has a church which dates back to the 11th century and a Calvary-Bell Tower from the 17th century. Its cemetery features Hilarri dating from the time of the bell tower.

The village is located on a secondary road of the pilgrimage to Saint Jacques de Compostela which passes on the highway to Ports de Cize, the priory of Saint-Palais to Saint-Michel-le-Vieux which had a hospice for pilgrims called Benta then to L'Hôpital-Saint-Blaise, Osserain, Pagolle, Roquiague, Haux, Larrau, and Ordiarp.

The commune has a primary school.

• Communes of the Pyrénées-Atlantiques department

• Ainharp on Géoportail, National Geographic Institute (IGN) website (in French)
• Ainharp on the 1750 Cassini Map