This trail starts above the village of Vilaflor. There is limited parking at the trailhead (possibly you can park a short distance in along the forest road). Alternatively, there is additional parking about 1/2 mile down towards Vilaflor past the second hairpin on TF-21.
This area is significantly drier than the north side of the island. It is part of the La Corona Forestal Nature Reserve and although covered in pine trees, they are somewhat sparse and not enough to provide much shade. You'll find some interesting cactus like plants though. And you'll have sweeping vistas of the coastline and the Atlantic Ocean almost a mile below you. Although you're riding on the south side of the el Teide volcano, you won't be able to see the summit from this ride.
The first 3.5 miles are relatively flat, but at this point you turn left at an intersection and the real climbing begins. You'll climb 250 m (800 ft) before beginning a descent towards TF-21. The trail finishes on TF-21 in a hair pin. Turning left onto TF-21 takes you downhill to the start of the ride presuming you've left a car.
If you want to add more miles (you'll probably invest a lot of time to drive here), you can continue straight along the forest road at 3.5 miles onto Vilaflor Extension
. This could be linked to the BC-4 Pinares de sur y volcanes negros
trail to make this into a much longer tour along the south side of el Teide.