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Infact entire Uttranchal is worth seeing,Its not that I am from the region and seen most of it but since I have seen most of India,USA,entire Europe including Communist countries.There may be lack of basic facilities in some places but it cud be ignored keeping in mind the beauty of the area.For pilgrimage no other state offer so many places in one state.Badrinath,Kedarnath,Gangotri,Yamunotri,Hardwar,Rishikesh,Si x Prayags(one on Kedarnath side and other five on Badrinath side),Tungnath,Poornagiriji,Hemkund,Reetha Sahib etc. etc.
For tourism the above places and then Auli,Joshimath,Bageshwar,Kausani,Almora,Binsar,Nainital.Ranikhet, Mussorie,Dehradun,Paataal Bhuvneshwar,Valley of flowers.For hiking and trekking-Pindari Glacier,Har-ki-doon etc.etc.
For holidays-Jim Corbett National Park.For quietness-Lansdowne.
Every place is worth seeing.