Set against a mountainous backdrop in the Salzkammergut region of Austria, Hallstatt has long been celebrated for its incredible natural and architectural beauty. It's not surprising, then, that Hallstatt is home to one of the most picturesque old towns in Europe. Its adorable market square and pretty old homes and churches have earned Hallstatt Old Town UNESCO World Heritage status. Come for a few days to soak up the scenery, or head here on a convenient day trip from Vienna for a quick visit.

Although Brussels may be the capital of Belgium, it's Bruges that’s most likely to steal travelers’ hearts, thanks to its pretty canals and its historic squares, churches, and museums. Highlights of this UNESCO-listed destination include Market Square, which is flanked by picture-perfect buildings, and Bruges City Hall, the city’s oldest structure. While the scenery alone is enough, Bruges offers plenty more: The city boasts great breweries and restaurants, plus a thriving lace-making tradition.

Mostar has one of the most aesthetically interesting old towns in the Balkans, with a dazzling mix of architecture, including everything from Ottoman mosques to 20th-century Secessionist structures. The city is best known for its Old Bridge, a popular launch spot for daredevil divers, but there is plenty more to see and do, from shopping in the 16th-century Kujundziluk (Old Bazaar) to visiting the historic Kajtaz House.

Just across the Czech border with Austria, Český Krumlov is among the most popular places in the Czech Republic, owing largely to the beauty of its UNESCO World Heritage-listed old town. The beautifully preserved medieval city's most famous attraction is its castle, a 13th-century fort perched on a hilltop. Its proximity to northern Austria makes it a popular destination for day trips from Linz; many people visit from Prague, too, either for the day or overnight.

If you’re looking for fairy tale scenery, consider a trip to Tallinn. While parts of the city certainly have a heavy Soviet influence, much of the enchanting Tallinn Old Town is still intact. Also known as Vanallin, this area is among the Estonian capital's biggest draws, owing to its medieval ramparts and well-preserved structures that have earned it a place on the UNESCO World Heritage list. Don’t leave before heading up to Toompea Castle, a centuries-old fortress that looks out over the city.

In southwestern France, Collonges-la-Rouge isn’t on the radar of many overseas visitors, but it’s a well-known destination for domestic tourists thanks to its characteristically red architecture, which gets its color from locally sourced sandstone. The town is a fun place to walk around and soak in the old-French atmosphere. Highlights include the Château de Vassinhac, a 16th-century castle repurposed as a hotel, and the Église Saint-Pierre, which dates back to the turn of the 12th century.

Despite its compact size, Valletta, the capital of Malta, is brimming with gorgeous architecture and is among Europe's most picturesque old towns. This fortified city is a UNESCO World Heritage site, owing partially to its dense concentration of historic monuments—there are about 320 spread across a mere 136 acres (55 hectares). Must-see attractions include the ornate St. John's Co-Cathedral and Fort St. Elmo, the latter of which helped keep the country safe during the 1565 Siege of Malta.

Edinburgh, the capital of Scotland, is famous for its festival season, which includes the celebrated Edinburgh Festival Fringe and the Royal Edinburgh Military Tattoo. It’s also a great place to celebrate New Year’s Eve, thanks to the annual Hogmanay festivities. Among the city’s claims to fame is the UNESCO-listed Edinburgh Old Town—home to top attractions including Edinburgh Castle and the Palace of Holyroodhouse, which are linked together by the main thoroughfare known as the Royal Mile.

While many visitors to Spain flock to hotspots such as Barcelona and Seville, those willing to venture further afield will be rewarded with the chance to see some truly special places, often with the added benefits of fewer crowds. One such spot is Cáceres in Extremadura, one of the prettiest historic towns in Europe. This UNESCO-listed city is dominated by architecture from the 14th to 16th centuries, including a mix of Roman, Italian Renaissance, Gothic, and Islamic styles.