Sinaia is generally very safe for solo female travelers. The locals are friendly and helpful and offer a warm welcome to tourists. Street crimes are relatively low and violent crimes are rare. Just like any other place, it is recommended to stay cautious and follow common travelling guidelines, such as avoiding deserted areas at night, staying aware of your surroundings, and securing your personal belongings. Always trust your instinct. Sinaia, with its beautiful Peles Castle, lush green parks, and ski resorts, is indeed a safe destination to explore.