You must visit Nainital in Uttarakhand . There are so many beautiful lakes in Nainital district like bhimtal saat Taal and the route is also very simple. you can book a train or bus till Haldwani or Kathgodam then it's 1 hour ride from there to Nainital.
Depends on which place you are going to visit in uttrakhand as there is so many places you can visit. And shimla is just a place in Himachal, If you can plan somewhere in Himachal then there is so many places which is far better then shimla.
PS: Uttrakhand wins if you going to compare only with Shimla.
I would prefer Rishikesh in Uttrakhand rather suggesting you Shimla, because according to me, Shimla is very over hyped and very crowded. There is not much connection with the mountains there, whereas Rishikesh is far better than the Shimla, you can find peace and calmness when you sit on the banks of Ganges.
Hi Sandep, Each and every place in HP & UK has its unique importance you have to decide how far you want to go and type of trip you want spiritual, religious, adventurous, bike trip or family trip, reserve forest visit etc
Broadly in HP dharamshala-McGang, Kullu-Manali, Shimla, Kinnaur, Lahaul-Spiti, Chamba-Dalhousie
In U.K. Nainital, Haridwar-Rishikesh, Dehradoon, Almora, Jim Corbet, Mosuri, CharDhaam, valley of flowers