Nainital is one of India's most popular tourist destinations - amongst hill-stations it is in all likelihood India's no.1 destination. And for good reason - the pretty Naini Lake with the mall around is no doubt the highlight of this beautiful town, but there are plenty of other great places too for the tourists. One such place that I quite like are the "Eco Caves".
The eco-caves are natural caves which have been slightly modified to allow for convenient human inspection. In total there are six caves, named after various birds and animals found in the Corbett National Park, which is a part of the Nainital district - for example, one of the caves is namedTiger Cave. It's a great experience entering this caves and will require some flexing of your body if you want to do all the six caves, as some of them will really require you to bend your body at difficult angles.
The cave complex consists of lovely gardens, a musical fountain and on the top of the complex is a small cafeteria, where you can quench your thirst and pick up some snacks. Overall, a great place and a must visit if you are staying in Nainital for two days or more.