We were at the Parador too in May 2001: They made the paperwork for getting the permit. So there was no need to make the long way to Santa Cruz!
I would strictly recommend to use mountain boots !. The trail is easy, but the volcanic rocks are sharp-edged, and the risc of a hurt is high!
Many mountaineers hike up to the Refugio Altavista, take the night there, and hike up in the early morning to see the sunrise from the top of Teide. That must be great and an exceptional experience! As far as I know, you do need a permit or resevation for the Refugio Altavista.
An other possibility to see the sunrise is to start about 1.5 or 2 hours before sunrise from the parking lot, and see the sunrise from the "Huevos del Teide": Huge black balls in a yellowish pumice-stone (Bimsstein) landscape, the view over the partly with red clouds covered ocean, created by the early sunlight - I'll never forget that!
IF YOU WANT KNOW HOW GO FROM THE SEA LEVER TO THE TOP IN ONLY ONE WALKING JOURNAY (3718 M) LOOK THIS PAGE:
Actually (november of 2004) the permission can be obtained coming the leader of the group to refill the information of the persons contributing photocopy of the DNI or passport of all of the members of the expedition. The schedule of the office of the National Park is 9 to 14h and it is necessary to choose among the groups of hours to access to the summit: 9-11h, 11-13h, 13-15h and 15-16h of 2 following days. According to the rapidity with which we come fewer hours will stay to choose.
Generally the inspectors descent in the last cable car at 16:30 and you can accede without permission to the path that leads to the top (as well before the 9am).
Out of the summer (as october, november, december...) with few people in the top after 14h or 15 h. the inspectors leave generally to climb to the mountaineers that have realized the effort to walk the 4 hours or more necessary to come up to the checkpoint (but it's a risk, it's better to obtain the permit).
This year we have done a climb to Mt Teide 3718 m from sealevel. The route is 29 km long and took us 6h and 5 min (we did it running). The route and the possibility of a climb from sealevel is not very well known and the loads of requests of information have given birth to www.teideascension.tk where everything is explained, from the route with maps and GPS points to the preparations, summit permit application etc.
If you visit it, better with ADSL, as documents are heavy and waitings may be long
La güeb de los que sube"n el Teide desde el nivel del mar
Playa del Socorro 0m - Pico del Teide 3718m
just back from a very nice time on teide. the refugio was open, not too warm but very welcoming. the warden said that they were aiming at keeping it open the whole year so if that proofs to be right everyone can look forward to a stay in that beautiful hut. i was surprised by the fact that not only were there beds but real bedcovers and pillows as well, so i need not have brought my sleeping bag. a headlamp however is handy!
Once you have a scanned in copy of your passport (which might also come in handy in case you should lose your passport) the easiest way of getting the permit is by email - email@example.com. You don't need to fill in the application form. You just have to give your name, passport number, the date you want to ascend, and the time span, and to attach the copy of your passport. You do have to submit your application AT LEAST 7 DAYS IN ADVANCE. You'll then get the permit within a couple of days, perhaps even the very next day, and can also print it out when you are on the road already.
I climbed Teide times last week (early March 2014).
Reservations for summit climbs are now booked online. Google Teide and reservation and you should find it.
There are present four official (allowed) routes to the summit:
1. Via Montana Blanca
2. From Roques de Garcia via Pico Viejo
3+4. From the western road via Pico Viejo.
I tried both 1 and 2 and found number 2 to be the most interesting. It is longer and there is 200 m additional climb, but the route is more varied and the views are in my oppinon nicer. When I hiked up both routes were not officially open due to ice and snow. This was not written anywhere except at the lower Teleferique station, but the routes were blocked from entry at the upper cable car station, so it might be a good idea to check at the lower cable car station before setting out.