Opened in 1978 to commemorate the celebration of nineteen centuries of the existence of the local council of Chaves, the museum is located in the mediaeval keep, offering an exhaustive display of the military history of Portugal, Chaves and its most relevant events and figures. It contains four rooms: on the first floor is the D. João I room, dedicated to the period of the Reconquest; the second floor is dedicated to the Peninsular Wars (1808-1815) in which Chaves played a leading role, as it was through this city that the Second French Invasion occurred (known as the War of Independence in Spain). The third floor is dedicated to Portugal’s contribution to the First World War (1914-1918), and finally the fourth floor is dedicated to the Colonial War (1961-1974), from where it is possible to access the top of the keep, from whose elevated pathway visitors can enjoy sweeping views over the city, the River Tâmega and the gardens that surround the mediaeval enclave.