Mont Valérien
From the Mont Valérien, Suresse, the French physicist Fizeau projected a lightbeam towards a mirror at Montmartre. Interposed in the path was a rapidly spinning cogweel with 720 precisely machined teeth. The beam would be exclipsed if the spin of the wheel was going faster. From this, Fiezau could calculate the speed of light as 315 400 km/sec. This was 1849!
Author: Dromos
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Hill

Château d'Agnou
The Château d’Agnou is a château, or manor house, situated in a place locally known as Bout d’Agnou in Maule, France. It is classified as a French historical monument.
In the 12th century, a castle called the Château Saint-Vincent was raised on the spot of the present manor. Built in the faubourg of Agnou, within the fiefdom of the Boutigny family, it stood outside the long walls that enclosed Maule. The Boutignys owned the castle from the 13th century on: first Hugues de Boutigny, Lord of Gavral, then his son Jean de Boutigny. However, it was later dismantled by order of King Louis VI. In 1357, the city was pillaged by Charles II of Navarre, who totally leveled the edifice. From then on, the barons of Maule lived in town, in houses constructed for them. This situation would change in the 16th century.
Author: Wikipedia
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Castle

Villepreux
Villepreux ) is a commune in the Yvelines department in the Île-de-France in north-central France located about 12 km west of Versailles, in the plaine de Versailles, almost in line with the perspective of the Grand Canal . The municipality, in low relief, is marked in the northern part of the depression of the valley ru Gally, and its tributaries, the ru de l'Oisemont and the ru de l'Arcy. The municipality is still largely rural. Urbanization is about 15% of the area, developed in the southern part, in the vicinity of Clayes-sous-Bois in the area served by railway services from Paris and Versailles.
Author: Wikipedia
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Municipality

Arboretum de Grignon
The Arboretum de Grignon is an arboretum located within the campus of the Institut des sciences et industries du vivant et de l'environnement on Avenue Lucien Brétignières, Thiverval-Grignon, Yvelines, Île-de-France, France. It is closed to the public but may be visited by groups.
The arboretum was established in 1873 by Pierre Mouillefert, professor at Grignon, who published in 1896 a pamphlet describing the arboretum at that date; however, it was lost in 1940. The arboretum grew gradually over time, with the most recent plantings between 1976-1978. Various of the trees were labeled in 1975 by Mr. George Callen of the Arboretum de Chèvreloup, and in 1991 Mr. Augustin Scalbert created a map identifying almost all trees. At that time, the arboretum contained approximately 230 specimens .
Author: Wikipedia
Arboretum

Chavenay
Chavenay ), also known as Vallon de Chavenay, is a commune in the Yvelines department in the Île-de-France region in north-central France. It is located close to Saint-Nom-la-Bretèche, Saint-Germain-en-Laye, and Versailles.Along with Crespières, Feucherolles and Saint-Nom-la-Bretèche Chavenay is twinned with Rösrath, Germany.
Municipality

Neauphle-le-Château
Neauphle-le-Château ) is a commune in the Yvelines department in the Île-de-France region in north-central France.Neauphle-le-Château gained international fame in 1978 when, on October 8, Iranian Islamic leader Ayatollah Ruhollah Khomeini rented and moved into a house there following his exile by the regime of Shah Mohammad Reza Pahlavi in the midst of the Iranian Revolution, and after being deported from Iraq where he was taking refuge amongst the Shi'a community. The Ayatollah continued to reside there until the following year when he returned to Iran following the collapse of the Shah's regime and later became Iran's Supreme Leader. Due to the Ayatollah's time residing in Neauphle-le-Château, the street in Tehran on which the French Embassy in Iran is located and was previously known as Faranseh street, is now renamed after the village. The property where he lived, at the corner of the Chevreuse Road and Jardins Path has long been fenced off and locked and the former dwelling is now destroyed.
Municipality

Saint-Germain-de-la-Grange
Saint-Germain-de-la-Grange is a commune in the Yvelines department in the Île-de-France in north-central France.

Forêt de Marly
The Forêt de Marly is a 2000 hectare forest estate in Yvelines, between Saint-Germain-en-Laye and Versailles about 15 km to the west of Paris. It is about 12 km long east to west, over the communes of Louveciennes, Marly-le-Roi, Saint-Nom-la-Bretèche, Feucherolles and others. Historically, it was a hunting estate of the kings of France, then of the presidents of the Republic, but is now divided along its whole length by the A13 autoroute.
Forest

Bazemont
Bazemont is a commune in the Yvelines department in Île-de-France France. It is situated 18 km south east of the town of Mantes-la-Jolie.

Le Pecq
Le Pecq ) is a commune in the Yvelines department in the Île-de-France region in north-central France. It is located in the western suburbs of Paris, 18.4 km from the center of Paris.The commune of Le Pecq is located in a loop of the Seine river, 19 km west of Paris, at the foot of the chateau of Saint-Germain-en-Laye.

National Archaeological Museum
The Musée d'Archéologie nationale is a major French archeology museum, covering pre-historic times to the Merovingian period. It is located in the Château de Saint-Germain-en-Laye in the département of Yvelines, about 19 kilometres west of Paris.The château had been one of the most important French royal residences in the Paris region since the 12th century. Following the move of the court to Versailles, the castle housed the court of James II of England in exile, became a cavalry school in 1809 and finally a military prison from 1836 to 1855. The château, which was in very poor condition, was classified as a monument historique on 8 April 1863.
Museum

Château de Saint-Germain-en-Laye
The Château de Saint-Germain-en-Laye is a former royal palace in the commune of Saint-Germain-en-Laye, in the département of Yvelines, about 19 km west of Paris, France. Today, it houses the musée d'Archéologie nationale .The first castle, named the Grand Châtelet, was built on the site by Louis VI in 1124. The castle was expanded by Louis IX in the 1230s.
Castle

Saint-Nom-la-Bretèche–Forêt de Marly station
Saint-Nom-la-Bretèche–Forêt de Marly is a railway station in the French commune of L'Étang-la-Ville in the département of Yvelines. Its name derives from Saint-Nom-la-Bretèche and the Forêt de Marly. It links to the CSO bus line 1.It is one of the termini of the Transilien Paris–Saint-Lazare, made up of one platform between two lines.
Trainstation

Rocquencourt
Rocquencourt ) is a former commune in the Yvelines department in the Île-de-France in north-central France. On 1 January 2019, it was merged into the new commune Le Chesnay-Rocquencourt. It is about 4 kilometres north-west of Versailles and 19 kilometres west of center Paris.The commune is mainly known as the location of a research unit of INRIA as well as a freeway exchange known as the Rocquencourt Triangle , which is often mentioned in traffic news.

Gambaiseuil
Gambaiseuil is a commune in the Yvelines department in the Île-de-France region in north-central France.

Millemont
Millemont is a commune in the Yvelines department in the Île-de-France region in north-central France.

Garancières
Garancières is a commune in the Yvelines department in the Île-de-France region in north-central France.

Gambais
Gambais ) is a commune in the Yvelines department in the Île-de-France region in north-central France. The commune is 58 km west from the center of Paris.

Montfort-l'Amaury
Montfort-l'Amaury is a commune in the Yvelines department in the Île-de-France region, north central France. It is located 20 km north of Rambouillet. The name comes from Amaury I de Montfort, the first seigneur of Montfort.Montfort-l'Amaury lies north of the Rambouillet Forest. It is located at the foot of low hills, at about 130 m above sea level.

Château de Thoiry
The Château de Thoiry is a 150-hectare castle, zoo and botanical garden that was opened to the public in 1965 in the village of Thoiry, France, with gardens and a zoological park. Located about 30 miles due west of Paris, it is best visited by automobile to take advantage of the drive-through lane. Its popularity has continued to grow—by 1974, over 280,000 visitors per year were coming to see an assortment of 1,000 wild animals.
Castle

Château de Groussay
The Château de Groussay is located in the town of Montfort-l'Amaury, in the Department of Yvelines, west of Paris, in France. The Château was built in 1815 by the duchesse de Charest, a daughter of Louise Elisabeth de Croÿ-Havré, marquise de Tourzel, the governess of the royal enfants de France of Louis XVI and Marie Antoinette.

Garches
Garches ) is a commune in the western suburbs of Paris, France. It is located 11.9 km from the centre of Paris.Garches has remained largely residential, but is also the location of Raymond Poincaré University Hospital, which specialises in traumatology, road accidents and physiotherapy.

Fort Mont-Valérien
Fort Mont-Valérien is a fortress in Suresnes, a western Paris suburb, built in 1841 as part of the city's ring of modern fortifications. It overlooks the Bois de Boulogne.Before Thiers built the fortress, Mont Valérien was home to hermits. Since the 15th century a community of hermits lived on the slope of Puteaux similar to the one of Chartreux: private cells, communal holy Mass and holy Office, perpetual silence. Manual labor and prayer divided the days equally.
Fortress

Château de Villiers-le-Mahieu
The Château de Villiers-le-Mahieu is a modernised castle in the commune of Villiers-le-Mahieu in the Yvelines département of France. It was built in the 13th century and was extensively remodelled in the 17th. It is now in use as a hotel.
According to legend, the original castle was built by the English in the Middle Ages. The original 13th-century castle moats surround the château. In 1642, the Marquis Claude d'Attilly built the present Renaissance style structure on the remains of the original. It was restored in 1965 by the Comte de Rohan Chabot and was the home of the French Expressionist painter, Bernard Buffet, from 1971 to 1979. In 1980, a young hotelier, Jean-Luc Chaufour, began a process of establishing a top class hotel within the castle and its grounds.
Hotel

Golf de Saint-Cloud
Golf de Saint-Cloud is a 36-hole golf complex located in the parishes of Garches, Rueil-Malmaison and Vaucresson, 12 km west of central Paris, France.Opened in 1913 and designed by well renowned English golf course designer Harry Shapland Colt, the Vert or Green course is a championship course commissioned by Saint-Cloud's then owner, an American lawyer named Henry Cachard. The Estate was previously owned by Empress Joséphine, Napoleon's wife.
Golf Course

Suresnes–Mont-Valérien station
Suresnes–Mont-Valérien is a railway station in the town Suresnes, Hauts-de-Seine department, in the western suburbs of Paris, France.
Trainstation

Pavillon du Butard
The Pavilion du Butard is a hunting lodge in the Forêt de Fausses-Reposes in the territory of La Celle-Saint-Cloud in Yvelines, France. Part of the gardens of Versailles, it was designed by Ange-Jacques Gabriel for Louis XV and built between 1750 and 1754. It was made state property on 27 June 1794 by François-Nicolas Périgon, notary at Paris, during the French Revolution. On 23 April 1802 it became the property of empress Joséphine de Beauharnais, who wished to merge it with her Malmaison estate, but it returned to being state property on her divorce from Napoleon in 1809. It was later also enjoyed by Charles X of France and emperor Napoleon III of France. It was occupied by the Prussians during the Franco-Prussian War. Still state property, it was made a monument historique on 29 August 1927.
Monument

Côte de Beule
RouteYou Climb Code : D_4_d
Length : 3.21 km
Ascent : 145 m
Average grade : 4 m / 100 m - 4.25 %
Maximal grade : 5.84 %
Author: Cols&Climbs@RouteYou
Slope

Château de Bagatelle
The Château de Bagatelle is a small Neoclassical style château with several small formal French gardens, a rose garden, and an orangerie. It is set on 59 acres of gardens in French landscape style in the Bois de Boulogne, which is located in the 16th arrondissement of Paris.
The château is a glorified playground, actually a maison de plaisance intended for brief stays while hunting in the Bois de Boulogne in a party atmosphere. The French word bagatelle, from the Italian word bagatella, means a trifle or little decorative nothing. Initially, a small hunting lodge was built on the site for the Maréchal d'Estrées in 1720.

L'Étang-la-Ville
L'Étang-la-Ville ) is a commune in the Yvelines department in the Île-de-France in north-central France.L'Étang-la-Ville is served by two railway stations on the Transilien Line L: L'Étang-la-Ville and Saint-Nom-la-Bretèche–Forêt de Marly.
Arrondissement

Daubes 137