- Macapá is the capital city of the state of Amapá in Brazil. It is located in the northern part of the country, near the Amazon rainforest. Macapá is situated on the northern bank of the Amazon River and is known for its unique geographical location, being the only Brazilian state capital that is crossed by the Equator. The city has a population of around 500,000 people and is the economic, administrative, and cultural center of Amapá. Macapá is known for its natural beauty, with rivers, forests, and wildlife surrounding the city. It is also a popular tourist destination, offering attractions such as the Fortaleza de São José de Macapá, a historical fortress, and the Marco Zero do Equador, a monument marking the Equator line.