Being watched

It has been a long day with a 4 hour guided walk around the city before a long coach journey of over 5 hours to a picturesque city in another country. This morning we had seen many buildings which were built at the beginning of the 20th century in the Art Nouveau style with very elaborate decorations. Faces seemed to abound but I was especially interested in these huge faces above the unusual blue tiled building of which there are very few in the world.
Where were we? Another clue tomorrow.