Chitwan in general, is a safe place for solo female travelers. The locals are friendly and helpful, and crime rates are relatively low. The main safety concern might come from travel-related scenarios such as trekking or wildlife safari where local guides should always be hired. Women in Nepal are treated with great respect and that also applies in Chitwan. However, as in any place in the world, it's always recommended to keep your valuable belongings secure and stay cautious, especially when traveling alone at night.