Dehradun is the capital city of Uttarakhand. It is approximately 250Km from Delhi and 170 Km from Chandigarh surrounded by mountains. Guchchu Pani is one of the famous tourist destination. It is approx 10 Km from ISBT Dehradun. You can book a cab or auto for 150-200 Rupees. It takes 45-60 minutes,depends on traffic, to reach there.
Guchchu Pani is a 2-2.5Km long cave where water flows up to the height of 1 feet. So you must have sleepers to walk on the pebbles. Parking charges are 10 rupees/hr and ticket of 25 rupees for 1 adult is necessary to get enter into it. It's opening timing is 7am in the morning to 7:30 in the evening all the days. You can enjoy swimming near to it in a Swimming pool.
This cave hardly takes 1-2Hr to visit. You can enjoy tea, snacks at the shop inside the cave. Extra clothes should bring with you because there are small waterfalls and you can't miss to enjoy it.
If you will stay close to nature, you will love you self. Everyone loves to enjoy with friends and experience of Cave with small water flow through your feet, greenery around makes it one of the loveliest moments of life.
Be careful to visit during rainy season. Water flow rate is very high and water level did not take much time to raise up.
These last two pics show the last point of the cave. You can see the clarity of water.
Have a nice and safe journey. Good luck.