The Certosa di San Martino, a former monastery complex turned museum in Naples, Italy, is a must-visit landmark perched atop the Vomero hill. Originally dedicated to St. Martin of Tours and expanded over the centuries, it now houses the National Museum of San Martino. With a fascinating display of Spanish and Bourbon era artifacts, as well as exquisite presepe (Nativity scene) exhibits considered among the world's finest, this place offers a unique blend of history and art that will leave visitors in awe.