The Loreto gallery was one of the five galleries that made up the system of the Águas Livres Aqueduct. Its length, all of it underground, was 2,835 metres and this included all its branches and canals.

The Loreto Gallery’s underground trajectory was as follows:

• Start at the Register house, adjacent to the Mãe d’Água das Amoreiras Reservoir on Rua das Amoreiras
• It descended following the line of Rua das Amoreiras up to Largo do Rato
• It followed the Rua da Escola Politécnica
• It followed the Rua D. Pedro V
• It carried on along Rua da Misericórdia
• It crossed the Largo do Chiado
• It carried on through Rua Paiva de Andrade
• It ended on Largo de São Carlos

Next to the former Colégio dos Nobres (Noble College), current Natural History Museum, there was a sink from where water was pumped to the Royal Press House and the Monte Olivete Fountain (former Arco de São Bento Fountain) and in the line of the Travessa da Mãe d’Água there was a square stone sink to separate the water that would follow on to the Século Aqueduct and the Praça da Alegria Aqueduct, whose extension supplied a public promenade fountain.

This gallery supplied some public institutions, of which we highlight the National Press house, the Public Promenade, the Misericórdia charity, the S. Pedro de Alcântara collection house and the Carmo Municipal Guard Barracks.

The Water Museum organises guided tours of the Loreto Gallery, which includes some underground sections:

• From the Patriarcal Reservoir to the São Pedro de Alcântara belvedere
• From the Patriarcal Reservoir to the Rua do Século