Rishikesh, the place which I personally love most in uttarakhand. The ambiance of rishikesh is like if you go there once you want to visit it again and again. The Ganga Arti is so good in the evening without any crowd... You can just sit and have magistic view. I mean of the all, ganga arti of rishikesh was the best (my personal views). The beautiful view of Ram Jhula and behind that the view of mountains in the evening is just can't be expressed in words it can be felt at the moment.
The city is 50-60km from Haridwar and 350km from Delhi. Bus is the good source of transportation, I would suggest personal vehicle as you can have the scenic view and click photos in between too. Please visit Neelkanth temple also it's 10 km from rishikesh, you can trek for that, it will take one whole day for place to visit.
The place is famous for its rafting and bungee jumping expedition. Moreover, you can have yoga classes and meditation classes there as people from all over the world prefer Rishikesh for these activities.
2-3 days are enough for this place and if you are very much exhausted from work and have more holidays I would suggest 4-5 days so that you can just live and get yourself rid of metro life.
I will rate the place 4.8/5. Very much recommend to visit.
