While its religious monuments are worthwhile sights, the main attraction in Avila are the walls that surround this city. My dad and I arrived from Segovia (see my review) quite late in the afternoon so I did not have time to see too much. Besides the magnificant walls, we managed to visit the interior of the San Vicente Basilica (under restoration but cheap admission and even comes with a free postcard) and the local cathedral (also under restoration but contains beautiful tombs). While walking on the walls was pleasant and a great way to see the surroundings, I have to concur with Frederik Dawson that the walls look a lot better from the ground. Avila's walls, along with their numerous churches, make this place a great WHS and one definitely worth visiting.