Spain's highest peak, on your own schedule, for a fraction of the coach-trip price.
Hire a car, drive up through the corona forestal into the moon-like Las Canadas caldera, stop at the Roques de Garcia viewpoint, then take the cable car near the summit if you fancy it. Leave the south by 9am and you will have the viewpoints nearly to yourself.
The cable car (Teleferico) sells out days ahead in season and closes in high wind. Book online before you go and check its status the evening before. No ticket? The viewpoints and short marked trails are free and still spectacular.
The final 163 metres to the summit need a free permit from the national park, released online months ahead. Most visitors skip it and lose nothing.