Absolutely not; in many ways, 23 is considered the "golden age" for travel. At 23, most people have a level of maturity and independence that makes navigating foreign transit and budgeting much easier than it is for a teen. You are still young enough to fit into the vibrant hostel culture and qualify for "Youth" discounts on rail passes (like Eurail) or museum entries, which often last until age 26 or 30. Unlike an 18-year-old on a "gap year," a 23-year-old traveler often has the benefit of a university degree or some initial work experience, which can open doors for working holidays in countries like Australia or New Zealand. Many solo travelers in hostels are in the 22–28 age bracket, so you will find yourself in the majority rather than the exception. Whether you are taking a career break or a post-grad soul-searching trip, 23 is the perfect time to build life skills that no office job can provide.