Built in the year 1009, the Saint-Martin church watches, like a benevolent and welcoming sentinel, over the Old Country, the oldest district of Sartrouville.
The church houses notable works of art such as "The Charity of St. Martin", depicting St. Martin, patron saint of the parish, on horseback, donating half his coat to the poor. It was classified in 1965 as an object in the inventory of Historic Monuments.