If India , try to be in north or north east. You can opt for water rafting at Rishikesh and then travel to Mussoorie. You can visit Tawang , Arunachal. You can also visit Cherrapunji and Dawki together.
Try visiting kuman, garwhal in himalaya. Both Uttarkhand and himachal have exhilarating places.uttarakhand is little different in vegetation and simpler vibes. Less commercial. Hillstaions lime. Munshiyari, kausani, kasardevi are offbeat and much more beutiful than any other places.. In himachal popular spots like Parvati, and McLeod is good to explore, but tirthan Valley gnhp is best for all kind of retreat and vacation.. Slow travel is the key to peace..i manage some off beat places and homestays in these mountains.. Lemme if i can help with itinerary.
Hey Dharini This is best Places you can visit in Summer In India 1- Manali ( Himachal Pradesh ) 2- Shimla ( Himachal Pradesh ) 3- Khajjiar ( Himachal Pradesh ) 4- Dalhousie ( Himachal Pradesh ) 5- Kasol ( Himachal Pradesh ) 6- Darjeeling ( West Bengal ) 7- Ooty ( Tamil Nadu ) 8- Nanital ( Uttarakhand ) In International 1- Bali ( Indonesia ) 2- Sri Lanka 3- Nepal Happy Travelling !!!