You can choose any place of your choice depending upon the connectivity from your origination of travel. I went to Ooty for my solo trip and it was exceptionally amazing! You can go for places in south India like Ooty, Kodaikanal etc. You can also start from UP visiting Banaras - Agra then onwards to other places in Rajasthan like Pushkar, Jaipur etc. Just be aware about your surroundings wherever you go and your experience will be great!