This surprising enoteca is located in one of the former buildings of the ancient Lisbon water supply system. The huge aqueduct with the enormous arches that you see when you drive into Lisbon from the direction of Cascais is also part of the same system. If you are interested you can visit the old basin (entrance in the middle of Jardim Príncipe Real).
In Chafariz da Mãe de Água the water is literally passing by your table. A great location. Here you can enjoy a glass of wine from their huge wine collection. Or stay a bit longer and try a bottle! They serve dinner as well.
They also offer wine tasting activities and other special offers such as Happy Hours. Check out their site.