The Cintura line (Portuguese: Linha de Cintura, formerly called Linha de Circumvalação de Lisboa) is a railway line in Lisbon, Portugal. The half circle route was opened in 1888[8] and serves as a connection between all railway lines in Lisbon: The Cascais, Sul, Sintra, and Norte Lines. There are two railway triangles, one in Sete Rios, and another in Xabregas. It crosses all four Lisbon Metro lines, and connects to three of those at four stations.[7]
Reis, Francisco; Gomes, Rosa; Gomes, Gilberto (2006). Os Caminhos de Ferro Portugueses 1856–2006 (in Portuguese). Lisbon: CP – Comboios de Portugal e Público-Comunicação Social S. A. ISBN989-619-078-X.