Although there are several national parks in India, most with tiger reserves, Jim Corbett National Park is the oldest, established in 1936 to protect the endangered Bengal Tiger.
Home to around 10% of India's estimated 1,500 tigers, it's interior includes forests and dense foliage that can make tiger sighting unreliable, however a visit in the early summer is your best bet to view a tiger emerging from the brush looking for water.
Safaris at Corbett fall into two transport types: by jeep or elephant-back. The jeeps range farther into the park, which can often result in more frequent tiger sightings.
Tiger sightings can be rare, so even if you do happen to miss out, it's entirely possible to catch sight of 50 other species of mammals.
Commonly seen animals include monkeys, wild elephants, various deer, sloth bears, peacocks, lizards, jackals, and macaques.
The beauty of the park makes it a destination in addition to wildlife watching. Located in the foothills of the Himalaya on the Ramganga River, the Corbett contains both dense forest, grassland, rivers, and valleys.
Various eco-tour packages are available from the Corbett National Park website.