Plaça Major, Banyoles, Spain
The pavements, the asphalt of the streets and the sandy soil in the squares were replaced by tessellated paving in travertine slabs. This rough, light stone formed by incrustations of moss and grasses in the calcareous stone where some springs emerge, is very present in the subsoil of Banyoles and is the main material used in the construction of its medieval buildings. In the new paving, the travertine slabs fold back on themselves, making way for the canals that are open in some discontinuous sections. Eventually the uncovered parts open out into more extensive sections, forming pools of now-clean water.
(Source: publicspace.org)