San Martín (Spanish pronunciation: [sanmaɾˈtin]) is a department and region in northern Peru.

The Pongo de Aguirre is an important canyon formed by the Huallaga going through the Andean hills.

Tupac Yupanqui entered and subdued the Inca dominion, the province of Moyobamba, known back then by its native name, Muyupampa.

The construction of a highway in recent years has increased the exchange of different products, benefitting the economy of this region.

The provinces, with their capitals in parentheses, are: Gran Pajáten is a pre Inca complex of circular slate buildings decorated with figures of flying condors situated on the border with La Libertad.