Patal Bhuvaneshwar is a completely thrilling experience. If you are a devotee or an adventurer, its a fulfilling experience for both kinds of travellers. You have to take a guide at the entrance of the cave (you can't do it without one) and he takes you in the underworld and guides you through it. Inside visitors will find naturally made structures like entire Shiva family including Lord Shiva, Ma Parvati, beheaded Ganesh, the Char Dhaams, the Mount Kailash, Adishesha Naag, creation of the universe, entire pantheon of 33 koti Gods and Goddesses, the coming down of Ganga, sages in their deep penance and description of four yugas including the indicator when the present Kaliyuga will come to an end with destruction of the world and coming of Satyuga. It takes more than an hour to get the entire narrative inside the cave
Timings: 8am-6pm (summes), 9am-5pm (winters). Batches of 60 allowed at a time (since entry and exit gates are same).
How to reach
1) Best is to have your own vehicle (can halt at any place, relax for a night and do the rest of the journey).
2) For others (tough route): Direct bus from haldwani bus depot (morning before 6am) to patal Bhuvaneshwar (runs thrice a week)- even the bus officials have no idea about this direct bus. Other option (better) is to catch direct bus from haldwani to gangolihat (6am). This will drop you 8km short of the cave temple at a T point. From here you can go in shared cab (Rs.20/pp) to patal Bhuvaneshwar.
3) Best journey by bus: Catch a bus to almora (unlimited buses available- go for govt. bus). Stay for a day and do the rest of the journey the next day (bus reaches at 9-9:30 am here for gangolihat/patal Bhuvaneshwar)
Stay: No too many options available.