When I came to Delhi we all went to Rishikesh which was hardly a 6-7 hours of ride. It truly is the best place to visit I feel, the atmosphere is filled with peace, spend your time at river bank, or go on small treks. Though winters are here Kasol still will be the place to go which I guess is a drive of 13-15 hours. This travel might take time but the outcome (destination) is worth the wait. Wandering in the streets, going on small treks or just chilling somewhere in the mountains! P.S. if you go to Rishikesh try staying in a tents on river bank, could be a bit expensive but at nights laying on the ground next to the river bank looking at the sky wrapped with star's blanket is always best.