Maas Fortress is a historical site located in Cisadane Village, Kwandang District, North Gorontalo Regency. The fort is thought to be the result of the Portuguese heritage of the 18th century. Its function is to control the security of waters in the Sulawesi Sea. Maas Fortress has an area of approximately 2 (two) hectares. The site is thought to have been built in the 1790s.
Maas Fortress has 4 (four) bastions where soldiers can monitor their enemies. The ruins of this bastion show an octagonal shape. The structure of the wall building is made of rock that can last a long time. The composition of the bastion structure is rock, andesite, tuff, breccia, granodiorite. The species is a mixture of crushed coral reefs and fine sand. The ceramic fragment was found at a depth of 52 cm from the ground surface at the beginning of the excavation on the southwest side.