For beauty & photography, National Tile Museum (Museu Nacional do Azulejo) delivers.
A quietly wonderful museum that explains the blue tiles you see everywhere, climaxing in a 23-metre panorama of pre-earthquake Lisbon and a jaw-dropping gold chapel. The catch: it's out east, off most itineraries, and 'a museum of tiles' undersells to those who don't yet care. Converts almost everyone who actually goes.