In the fifteenth century, a building/tower was erected at a distance of roughly six metres from the tower of Porto Cathedral, [...]. this new tower was intended to house

theTown Hall, known by the name of Casa dos Vinte e Quatro, since it was also used for meetings of the Guilds and Corporations.

This building, which is known to have measured 100 spans in height, with a room at the level of the cathedral square, and another at the level of Rua de S. Sebastião, suffered various accidents until it finally disappeared almost complete disappearance.

Recently, the area has been subjected to excavations and some walls have been restored, which has made its possible original form much clearer. 

[...] the proposed design is intended to transform the building into a memorial recalling the long life and history of the city of Porto, through the creation of an architectural object evocative of the previously existing tower, placed in dialogue with the remaining towers of the Cathedral and the Historical Archive and endowed with an internal space that can excite its visitors by reminding them of such a glorious past.

A structure with U-shaped walls, resting on part of an existing ruin, borders the building on three sides, while the fourth is open [...] and permits a reading of the city. While the external volume of the new building-object [...] suggests the size and shape of the evoked tower, its internal space, whose entrance is directly opposite the

cathedral, spreads vertically upwards, allowing us to sense its height of 100 palms, partly served by a double staircase, and also looks out directly over the city, which

[...] offers itself up for contemplation.

The granite in both the exterior and interior walls, the Corten steel in the pillars and beams, the brass in the frames of the double-glazed windows or the chestnut lining the floors and stairs, all of these materials come together to reinforce the sober expression of the spaces which, both inside and outside, accompany and condition the visitor’s movements. [...] The design contemplates the redevelopment of an area that provides access to the cathedral through Calçada de Vandoma and the complete rearrangement of the area around the memorial in order to give greater prestige to the most noble site in the city of Porto and to introduce a new reading of the place.