A day in Tenerife

[Trendsetter]

This week I'm going to Tenerife for the weekend as part of a group. I'm going a day earlier than everyone else so the first day will be spent on my own.

Can anyone recommend any must do activities? Is it worth hiring a car to go anywhere in particular? I'll be staying in the South of the island but don't mind travelling around

[Trendsetter]

Funnily enough I had seen that they do tours of the mountain which I thought sounded good, especially the night tour. The company I found said it takes 7 hours which is quite the day but it does look like it would be spectacular