The “Arcos da Lapa,” as the famous Lapa Aqueduct in Rio de Janeiro is known, celebrated its 80th anniversary as officially registered Brazilian Cultural Heritage on April 5. Declared a protected heritage site by the National Institute of Historic and Artistic Heritage (Iphan) in 1938, the location, also known as the Carioca Aqueduct, is one of Brazil’s most notable architectural works and one of the city’s most recognized attractions.
The Aqueduct, considered the largest construction project undertaken in Brazil during the colonial period, was built of stone masonry and consists of 42 double arches, each 17 meters high, extending over 270 meters. The complete architectural ensemble includes the arches themselves, the public sidewalk beneath 
them, the National School of Music, and the Church of Our Lady of Lapa. The area is also famous for its various cultural and gastronomic attractions in Lapa, the most famous bohemian neighborhood in Rio.
Built in the 18th century, the aqueduct served both to bring water from the springs of the Carioca River to the city and as a passageway between the hills of Santa Teresa and Santo Antônio. Later, it became a viaduct for the trams that circulate through the Santa Teresa neighborhood in Rio. The structure was inspired by Roman arches and the Águas Livres aqueduct in Lisbon.
Source: www.brazilgovnews.gov.br