The municipality covers an area of 34.42 km2 (13.29 sq mi) of which 0.63 km2 (0.24 sq mi) is water. It comprises the town of Leerdam, the rural villages Kedichem, Schoonrewoerd and Oosterwijk. The south border of the town is formed by the river Linge. Leerdam is the most eastern town of the province of South Holland and is situated almost exactly in the middle of the three highways A2, A15 and A27.
Leerdam received city rights in 1407. The small river Linge, bordered by beautiful water meadows, defines the atmosphere and tone of the landscape. Several centuries ago Leerdam formed a part of the Vijfheerenlanden domain, before it was raised to the level of County in 1498. The rich history of Leerdam can be found in well-kept historic buildings such as the Grote Kerk (Great Church), the Hofje van Mevrouw van Aerden (Mrs. Aerden Almshouses, now a museum), the remaining and restored city walls on the Zuidwal and the Oude Raadhuis (Old City Hall).