Monkeys are going for your peanuts and bananas, which you can buy downstairs in several shops
Travel photography
Family-friendly: true
At your arrival to Batu caves you will be greeted by lots of monkeys. We noticed that the monkeys could be quite aggressive if you have food, best not to carry any food up there. The monkeys inside are fun, but somewhat creepy at the same time (one started attacking a tourist out of nowhere - the tourist honestly did nothing provocative and even had his back facing the monkey).
The most interesting part of the visit was when a temple worker put some food out for the monkeys; it was quite entertaining to see the greedy male monkeys eating all the food while the smaller monkeys jumped about to steal a bite.