San Martín is a department and region in northern Peru. Most of the department is located in the upper part of the Peruvian Amazon rainforest. Its capital is Moyobamba and the largest city in the department is Tarapoto.

La Libertad is a department and region in northwestern Peru. Formerly it was known as the Department of La Libertad. It is bordered by the Lambayeque, Cajamarca and Amazonas regions on the north, the San Martín Region on the east, the Ancash and Huánuco regions on the south and the Pacific Ocean on the west. Its capital is Trujillo, which is the nation's third biggest city. The region's main port is Salaverry, one of Peru's largest ports. The name of the region is Spanish for "freedom" or "liberty"; it was named in honor of the Intendancy of Trujillo's proclaiming independence from Spain in 1820 and fighting for that. It is the ninth smallest department in Peru, but it is also its second-most populous department after Piura and its second-most densely populated department after Lambayeque.