Canton of Montmorency

Communauté d'agglomération Plaine Vallée is the communauté d'agglomération, an intercommunal structure, covering northwestern suburbs of Paris. It is located in the Val-d'Oise department, in the Île-de-France region, northern France. It was created in January 2016. Its seat is in Montmorency. Its area is 74.1 km2. Its population was 182,585 in 2018.

Montmorency (French pronunciation: [mɔ̃mɔʁɑ̃si] (listen)) is a commune in the Val-d'Oise department, in the northern suburbs of Paris, France. It is located 15.3 km (9.5 mi) from the center of Paris. Montmorency was the fief of the Montmorency family, one of the oldest and most distinguished families of the French nobility. It is now a wealthy suburb of Paris.

The Cimetière des Champeaux de Montmorency, at Montmorency, Val-d'Oise in Île-de-France, is a cemetery first established in the 17th-century. It has the particularity of being the largest Polish burial place in France, hence its appellation as the "Pantheon of the Polish Emigration". It is located 15 km north of Paris and adjacent to the spa resort of Enghien-les-Bains. That it fell to Montmorency to become the main necropolis of the Polish diaspora in the country is due to two Polish political exiles, who happened to be staying at the nearby spa at the time of their death and were buried in the local cemetery. They were the statesman and poet, Julian Ursyn Niemcewicz, one time Polish envoy to the United Kingdom and Karol Kniaziewicz, politician and brigadier general in Napoleon's Grande Armée. Since their interments in the early part of the 19th-century, a succession of noted exiled Poles found their final resting place in the cemetery. There are over 276 Polish burials, among them the poets Adam Mickiewicz, the national bard, and Cyprian Kamil Norwid, statesman Adam Jerzy Czartoryski, and the diplomat and head of the Polish resistance in France during WWII, Aleksander Kawalkowski. The cemetery has become one of the national symbols of Polish resistance to all forms of oppression, and each Spring, it is the rallying place for Poles living in the Paris area, who go there to commemorate their historical leaders and artists.

The Château de Montmorency was an 18th-century mansion in Montmorency, Val-d'Oise of which today only a few vestiges remain.

The Fort de Montmorency was built following the Franco-Prussian War to defend Paris. Located to the north of Paris in Montmorency, the fort was part of an outer ring of fortifications built in response to improvements in the range and effectiveness of artillery since the construction of the Thiers fortifications of the 1840s. It was built between 1875 and 1879 in accordance with improved principles of fortification developed for the Séré de Rivières system. The fort defended its neighbors, the Fort de Domont and the Fort de Montlignon, as well as the town of Saint-Denis. The fort saw no action in the first or second world wars, but its prominent height made it ideal for use as a telecommunications relay station. In 1947 the French Air Force occupied the site, and by 1952 communication cables were installed to link the fort to the national air defense communications system. In 1956 the Fort de Montmorency became the national headquarters for Air Force communications. The fort was designated Base aerienne 285.Base aerienne 285 was disbanded in 1968 and the fort was first placed under the jurisdiction of ''Base aerienne 104 at Le Bourget, and later under the control of the French Air Force hardened command center at Base aerienne 921 at Taverny, at the west end of the Montmorency forest. From 1992 the fort has served as a training center for security forces associated with the Taverny center, the Centre d'Initiation aux Techniques Commandos.The fort remains occupied by the military and is not open to the public.

Deuil-la-Barre (French pronunciation: [dœj la baʁ] (listen)) is a commune in the northern suburbs of Paris, France. It is in the Department of Val-d'Oise and the arrondissement of Sarcelles. It is 13.7 km (8.5 mi) from the centre of Paris. Despite this proximity to the metropolis, Deuil has retained much of the charm of a country village, with orchards and wooded hillsides.

Soisy-sous-Montmorency (French pronunciation: [swazi su mɔ̃mɔʁɑ̃si] (listen), literally Soisy under Montmorency) is a commune in the Val-d'Oise département located 15.3 km (9.5 mi) north of Paris, France.

The canton of Deuil-la-Barre is an administrative division of the Val-d'Oise department, Île-de-France region, northern France. Its borders were modified at the French canton reorganisation which came into effect in March 2015. Its seat is in Deuil-la-Barre.It consists of the following communes: Deuil-la-Barre Groslay Montmagny Saint-Brice-sous-Forêt

Enghien-les-Bains is a railway station in the commune of Enghien-les-Bains (Val-d'Oise department), France. The station is served by trains of the Transilien Paris Nord line H, from Paris to Pontoise and Persan-Beaumont. The daily number of passengers was between 7,500 and 15,000 in 2002.

Deuil – Montmagny station is a railway station in Deuil-la-Barre, France, that also serves Montmagny. It is situated on the Épinay-Villetaneuse–Le Tréport-Mers railway, between Gare d'Épinay-Villetaneuse and Gare de Persan-Beaumont. It is served by Transilien trains from Paris-Nord to Persan-Beaumont and to Luzarches. The daily number of passengers was between 2,500 and 7,500 in 2002. The station has 145 free parking spaces. (in French) The station was opened in 1877, when the Épinay-Villetaneuse – Persan-Beaumont section of the Épinay-Villetaneuse–Le Tréport-Mers railway was opened by the Compagnie des chemins de fer du Nord.

Enghien-les-Bains (French pronunciation: ​[ɑ̃ɡɛ̃ le bɛ̃]) is a commune in the department of Val-d'Oise, France. It is located in the northern suburbs of Paris, 13.5 kilometres (8.4 mi) from the centre of Paris. Enghien-les-Bains is famous as a spa resort and a well-to-do suburb of Paris, developed in the nineteenth century around the scenic lake of Enghien. A casino, the only one in the vicinity of Paris, is located on the shores of the lake.

La Barre – Ormesson is a railway station in the commune of Deuil-la-Barre (Val-d'Oise department), France. The station is served by Transilien H trains, on the lines from Paris to Persan-Beaumont and Pontoise. The daily number of passengers was between 2,500 and 7,500 in 2002.