volubilis-moist-mosaic
Mosaic, natch.
Some areas were half-hearted roped off, and it seems that most people respect this. On the other hand, these mosaics that have been excavated are considered to be in fantastic condition, but no effort seems to be made to cover them or protect them from the elements (previously they were protected by being under some amount of sand and soil).
Evidently the previous guide through here had ducked in to pour some water on the tiles to demonstrate the richness of the colour still present.