At only 19 kilometers from Paris, Longjumeau draws her features in the department of Essonne. Originally located on the Roman road from Paris to Orleans, the city owes its initial expansion to the ford and became over time a mandatory stop for all market exchanges. Urbanization today from Yvette river to go up to the heights which were built residential areas of the city.
Framed in the extreme southeast by the forest Templar and a vast plain in east-central, Longjumeau lost its rural character and is fully integrated in the Paris suburbs.