The Roman Dam of Belas is a 3rd-century Roman barrier constructed to serve the city of Olisipo, located in civil parish of Queluz e Belas, municipality of Sintra.
Wikipedia https://en.wikipedia.org/wiki/Roman_Dam_of_Belas
Address Estrada das Águas Livres, 2650, Portugal
Coordinates 38°47'35.602" N -9°14'39.99" E
