Yes, Lo-Manthang is part of Nepal. It is a rural municipality in Mustang district in Gandaki Province. Also, known as the walled city of Upper Mustang, Lo-Manthang is situated in the rain shadow of the Annapurna and Dhaulagiri ranges. As the region successfully managed to keep the Chinese outside its borders over the past century, the entire region has preserved Tibetan culture for years.