This commune covers an area of 24km² and has around 500 inhabitants who are known as ‘Cosins’. It is located 17km south-west of Troyes and can be reached via the D53 or the D34. Situated about ten kilometres from the N77 and junction 20 (Torvilliers) of the A5, it is very close to major routes from Auxerre and Paris.

The town has a primary school, and also benefits from a number of active clubs and associations. Animations Cosines organises regular events that bring the community together, and the fire-fighters’ friendly society takes part in events, and organises the midsummer bonfires for St John’s eve and a Christmas event. Along with these major events, a club for rural old people meets every Tuesday.

The church of the Assumption was built between 1750 and 1760 to replace two other churches which were built on a different site and which burnt down in 1705 and 1749. Despite its 18th-century construction, the architecture is reminiscent of the previous churches and has a ribbed vault ceiling. Nonetheless, the church shows evidence of the 18th-century craze for Graeco-Roman antiquity with the pilasters and pediments that both surround the main doorway and can be seen on the interior walls. In this way, neoclassicism is combined with religious architecture. In 1986, the church was classified as an historic monument in recognition of these precious 18th-century artistic features. About twenty objects that are preserved in Vauchassis church are classified as historic monuments, including the 18th-century red and grey marble high altar, a painted wooden panel entitled Ecce Homo from the Dutch School dating for the first quarter of the 17th century, an 18th-century oil on canvas of the Immaculate Conception after Edme Bouchardon, and a 19th-century wooden reredos.

In the middle of the village, in front of the Mairie, a first world war soldier carrying a flag stands on top of a plinth as a memorial to those killed in both world wars.