On a hill above the Danube, Melk Abbey is one of Europe’s built marvels, a UNESCO World Heritage site, and one of the most important works of Baroque architecture in the world. Originally a palace, Leopold II presented it to a Benedictine order in the 11th century. The fortified abbey suffered both during the Reformation and the Ottoman invasion of 1683, and it would only reach its full splendor when it was restored and expanded at the beginning of the 18th century, complete with magnificent frescoes by Johann Michael Rottmayr. Long a center of learning, its 100,000-volume library remains an invaluable resource for scholars. The abbey, with its soaring church, marble hall, and museum filled with gilded riches are dazzling in their opulence and scale. When you then return to your Uniworld ship, with just 130 passengers, you’ll be reminded that an intimate atmosphere and impeccable service can be exquisite too.