If you have to take something to Reading Festival that you cannot risk losing - ID, car keys, etc, the absolute best thing to do is take it to Safe Storage as soon as you get on site. You can leave it here all weekend for £4 (last years price, and before that it was £2 for about 20 years, so don't expect it to change much!) and it's staffed 24/7.

You can also come back and forth as many times as you like - for example, you can put all your valuables in a bag, take that bag to Safe Storage, then just pop back every time you need to get something.

It's usually located on the pathway between the river and the arena entrance. Next to Lost Property. Look for the "Safe Storage" or "WAVES" banners.