Lisbon Cathedral (Sé de Lisboa)
An austere Romanesque building from the outside, the Lisbon Cathedral (Sé de Lisboa) has some lovely treasures inside. It dates from 1150 and was built this solidly to repel attacks from the Moors. It didn't do much to ward off earthquake damage in 1344 and 1755 and the cathedral we see today has been much repaired.
Inside you'll find the font where Saint Anthony of Padua is said to have been baptized in 1195 and a 14th century chapel by Bartholomeu Joanes. But its in the sacristy that the real treasures are found: relics, icons and 15th and 16th century religious art. The medieval cloister is also worth a look.
There are two routes. The red route does the old Lisbon loop and the blue route does the newer neighborhoods of Lisbon. Unless you want to go to the Aquarium, the blue route didn't seem worthwhile. The red route goes by a lot of the sights in the sightseeing book - monument to the explorers etc. However there is a lot of time there is no commentary and the same Portuguese song is played over and over and over again! Neither route gets close to the cathedral or castle, so if you are interested in those sights, you will still have some uphill walking to do.
Located in the Alfama district, it's best to catch tram 28 to Graca. To see the Cloister and Sacristy there is a small cost and it closes for lunch from 1pm - 2pm.