Tapkeshwar Mahadev Temple is a popular cave temple dedicated to Lord Shiva. It is situated on the banks of a migratory river, 5.5 km from the city bus stand in Dehradun. Tapak is a Hindi word, which means to drip. It is said that the water drips naturally from the ceiling of the cave on the Shivling, which is enshrined in the temple.
According to a legend, it was through this cave temple that Lord Shiva, made milk flow to Ashwathama, the son of Guru Dronacharya, the famous saint from the Indian epic, the Mahabharata. The temple is surrounded by sulphur springs, the water of which is said to possess medicinal properties. On the Hindu festival of Shivaratri, a large number of devotees visit this temple, to be a part of the sacred marriage ceremony of Lord Shiva and Goddess Parvati.