Castelo can be defined as the region between Rio Branco Avenue, Santos Dumont Airport and 15 de Novembro Square (Praça XV). The area is well known because it is located where once stood Morro do Castelo. The hill sheltered the first walled fortress in the city of Rio de Janeiro and was put down in 1922, as part of the reforms which began in the early 20th century.
In the early days of the city occupation the area of Praça XV was known as Praia da Piaçaba. The square had its name changed a few times and it was only with the proclamation of the Republic that the name Praça XV de Novembro became official. The square housed the port of the city from the 16th century to the mid-1770s, when Valongo's Wharf was then built.
Praça XV has buildings that recall the second half of the 18th century. Many official properties of the Colonial and Imperial government as well as churches and chapels were built around it, such as the Palace of the Governors, Casa da Moeda and the Royal/ Imperial Palace. Currently, the region stands out for its gastronomic, historical and cultural scene, bringing together different cultural centers, restaurants and entertainment options.