Massangano, Kwanza Norte, Angola
Located on the highest mount near the Kwanza River the fortress dates back to the late 16th century (1583) with several additions in the first half of the 17th century. Its builder(s), date and plan are unknown. Cadornega, who was stationed there for several years, bequeathed us the most thorough description of the square-plan stronghold with 23.5 side metres, its annexes and bastions, its trenches and ditches. It is a structure of thick stone walls with a gateway on the land side topped by a curvilinear pediment. The interior included the tile roofed annexes. The defensive scheme was completed with the Fort Saint John on a nearby outcrop and a series of trenches and ditches protecting access to the Lucala River. Within these walls the whole population of free men and slaves could be sheltered. The fortress was officially classified as a National Monument in 1923.