Well, I have been to many places, most of them includes Himachal and Uttrakhand region, but when it comes to only a weekend trip, I prefer to go to Nainital.
The city of lakes has its own charm and soothing environment, where one can take rest in the arms of peace. Well, you must be aware about various places already which you can explore in nainital, but the place I am going to tell you is completely a hidden gem.
Allu khet a place situated at a distance of 4 k.m from nainital bus stand. It's a beautiful track and you don't have to climb anywhere because most of the track is plain. You will pass through a dense forest which even does not allow sun light to pass through it, make sure a leopard is not following you(kidding) but yes at this place there are high chances that you can have a glimpse of wild life.
At the end of the track there is a temple and just above the temple,one can have one of the most beautiful view of his/her life, a bottle or a cup of coffee would be a great partner.
Enjoy friends :)