South of the Massif Central, the Lot forms a tributary of the Garonne on the right bank. The river that bears the name Òlt in Occitan gave its name to two French departments: Lot and Lot-et-Garonne. It constitutes the second longest river nationwide after the Marne, with a course 301 miles long (485 km), and crosses five departments: Lozère, Aveyron, Cantal, Lot, and Lot-et-Garonne. The Lot has its source on the southern slope of the Goulet mountain in the Lozère department and flows into the Garonne in the Lot-et-Garonne department.