When my wife and I visited Tenerife in the spring of 2008, our intention was, amongst others, to climb El Catedral, one of the Roques de Garcia. After we landed, we visited the local climbing store in Granadilla de Abona, bought the topo ("Principales Zonas de Escalada en Roca", a booklet with beautiful pictures but, unfortunately, not much information about the routes) and talked with a local about the climb.
We visited El Catedral for a closer look, but it felt a little dicey: I didn't see the route very well and I couldn't spot any bolts (there's supposed to be some bolted belays for abseiling). This, combined with my meagre rack (I had to leave most of my stuff home because of the 20 kg limit) and short abseiling span (30m with a 60m single rope), made me decide to keep El Catedral in store for a future visit.
Our topo included routes on other of the Roques de Garcia. Felix Mendez is one of the smaller ones. It has a couple of short routes (2-3 pitches) on steep volcanic rock. When I saw people abseiling from the shoulder of the rock, I knew there was a convenient way to get down. Time to try it :-)
Drive to Canadas el Teide and park near the hotel. Walk to the Round Tour of the Roques del Garcia. On the end of the parking, you can choose to go straight and descend into the basin or head right. Head right. After 10 minutes or so you'll see an outcrop some 70 meters high with a broad summit. The path passes the outcrop on its right side. When on the other (northern) side, turn around. The route starts in the middle of the face, below the summit.
1st pitch: climb a bolted face to the right of a pillar. Belay at a small ledge with two bolts (III/IV).
2nd pitch: from the ledge, climb a slightly to the right curving chimney on its left side. After 10-15 meters or so, cross the chimney and climb to the right of it. Select a spot for a belay. There are no bolts in this pitch. When making a belay, beware the loose stuff! I've never seen so much loose rock in such steep terrain (IV).
3rd pitch: a small pitch, which can be avoided if you don't mind rope drag. Keep to the right of the chimney and climb up until you reach the top ridge. Descend a few meters to the right (following the ridge) to the double bolt belay station (III).
From here, you can abseil to the shoulder (10-20 meters) and walk back to the track.
(you could also ascend the ridge to the left to gain its summit, however - again - you'll have to watch out because of all the loose stuff, especially where the chimney ends. The summit of Felix Mendez is a ridge of broken rubble. I haven't seen any bolts there)
Take a set of stoppers and some camalots/friends (middle-sized). I found my set of tricams very handy.
A helmet is absolutely essential!
A 60m single rope will suffice to abseil from the shoulder.