It's best to go to either Himachal, Kashmir, Nepal or Uttarakhand or similar places where you can trek to the Himalayas, and get into interaction with local people there. Who knows better than the local people about the hidden places of their native.
To see the hidden places of himalayas, the best place to visit is Kashmir. You can see many altitude lakes there. If you have heard about " the great lakes trek" its in Kashmir only