Caves
Grutas de Mira de Aire
There are several caves worth visiting while on route to Grutas de Mira de Aire. For example Alvados and Grutas Santo Antonio, but the Grutas de Mira de Aire are the most spectacular.
If you ignore the tacky fountain at the end, the walk down into about a mile of caves beforehand will far surpass anything you've seen at Cheddar Gorge.
And the good and welcome news is that after walking downhill for about a mile, there is a lift to take you up the height of a ten story building back to the surface again only a few hundred yards from where you started.
If planning a visit to Fatima, Batalha, or Porto do Mos, be sure to make a tiny detour and visit these caves. There is also an Aquapark there for the kids to cool off after a a (probably) hot drive into the inerior.

