Osny: Discover the Château Park, Museums and Trails

Osny is home to the Château de Grouchy, a neoclassical château, historic church art and an expansive park in the heart of the town centre. The château dates from the late 18th century; it was listed as a protected site in 1945 and added to the supplementary inventory of historic monuments in 1990.

Culture and History

The Château de Grouchy is a cultural centre that regularly hosts concerts, conferences and exhibitions, as well as a permanent gallery. The landscaped park includes a French garden, a dovecote, terraces, statues, a temple of love, a kitchen garden, an ice house and a pond.

The Église Saint-Pierre-aux-Liens is a Gothic church built in the 13th century, probably on 12th-century Romanesque foundations. After being destroyed during the Hundred Years’ War, it was rebuilt and consecrated in 1479. The choir was added to the inventory of historic monuments in 1926 and its bell tower in 1948; a later interior renovation uncovered frescoes and remnants of 16th-century polychrome decoration.

Museums

The Musée William-Thornley, located in the attic of the Château de Grouchy, is a public collection dedicated to the post-Impressionist artist William Thornley. More than 200 drawings, lithographs, watercolours and paintings are displayed in rotation during temporary exhibitions. A selection of his works can be seen there; William Thornley is considered underrepresented in national collections.

The Musée William Thornley also displays works by Alexandre René Véron, Jules-Jacques Veyrassat, Camille Pissarro and Edmond Eugène Duc. From the Osny stop on line J, bus 35 runs to the Château de Grouchy stop; alternatively, you can walk through the Parc de Grouchy to the museum. The Musée William-Thornley welcomes groups by prior arrangement.

The Musée départemental des sapeurs-pompiers has been housed in the former stables of the Château de Grouchy since 1999. Visitors can learn about the development of the firefighting profession from the 18th century to the present day. The collections on display at the Musée départemental des sapeurs-pompiers du Val-d’Oise include hand pumps, motor pumps, vehicles, uniforms and firefighting equipment.

The museum has a room specially intended for children, with an extensive toy collection; the oldest pieces date from the 19th century.

Nature and Trails

The Parc de Grouchy is a 39-hectare green space in the centre of Osny. It offers large lawns framed by wooded areas, as well as an extensive network of waterways.

Osny’s nearly 16 kilometres of hiking and walking trails include paths through the Parc de Grouchy and along the banks of the Viosne; paths lead from the park to the hamlet of Immarmont. In the Parc de Grouchy, you can go jogging in the morning, relax and take family walks, with a stop at the carousel along the way.

Historic buildings, changing museum themes and trails through green spaces offer different focuses for planning a day in Osny.

Other Places

Other places in the same regional area: Roissy-En-France, Le Thillay, Seraincourt, Villers-En-Arthies, Omerville, Vienne, Pierrelaye and Ermont.

For the broader travel overview: Val-D'oise.