2. The Sanctuary of Las Lajas, Ipiales, Colombia (1949)

A neo-Gothic church hanging 150 feet above a dizzying canyon of the Guáitara River - at the site where the Virgin Mary is said to have appeared before a woman and her daughter, caught here in a violent storm.

3. The Church of Saint Sava, Belgrade, Serbia (2020)

Unusually magnificent for the 21st century, but proof it can still be done in the modern age. This massive Orthodox church, built to rival the mighty Hagia Sophia, boasts a 50 million-piece mosaic, the largest in the world.

4. The Sanctuary of Madonna della Corona, Spiazzi, Italy (c.1625)

Nestled somewhere between Heaven and Earth. In c.1000 AD, a dwelling was hewn into the rock here by monks from nearby Verona. After much iteration, it's now a minor basilica with a stunning 19th century facade.

5. Borgund Stave Church, Lærdal, Norway (c.1200)

An iconic stave church; initially Catholic, then Lutheran. It's built entirely from wood, yet has stood for more than 800 years. The builders didn't use any metal nails - it's held together instead by wooden dowel pins.

6. The Church of the Transfiguration, Kizhi, Russia (1714)

Another exclusively-wooden wonder with 22 magnificent domes. The 18th century original (subsequently restored) was also built without nails, instead using horizontal logs that interlock in the corners.

7. Sagrada Família, Barcelona, Spain (ongoing)

An exercise in intergenerational construction - Gaudí's unique design has been under construction for almost 142 years. When it's finally finished (projected to be 2026), it will be the tallest religious building in all of Europe.

8. The Expiatory Church of the Sacred Heart of Jesus, Barcelona, Spain (1961)

A neo-Gothic masterpiece on the summit of Mount Tibidabo. It was built there to prevent a Protestant church and hotel-casino being erected on the highest point above the city.

9. Boston Avenue Methodist Church, Tulsa, USA (1929)

Among the most famous American Art Deco designs ever realized, featuring a soaring 225-foot tower. It captured the spirit of the Roaring Twenties impeccably, finished just before the country plunged into the Great Depression.

10. Clermont-Ferrand Cathedral, France (13th - 19th century)

An imposing Gothic masterpiece built entirely from black lava stone. The 315-foot twin spires dominate the city's skyline, making for a striking view for miles upon miles.

11. The Palatine Chapel, Palermo, Italy (1143)

An exquisite chapel within the Palazzo Reale in Palermo. The mix of styles (Byzantine, Norman and Fatimid) is highly unusual, and the gold mosaics are so intricate that even the figures' fingernails can be clearly made out.

12. The Cathedral Basilica of Saint Cecilia, Albi, France (1480)

The largest brick building in the world. Don't be deceived by its fortress-like exterior - inside is one of the most elaborate and breathtaking ceilings in the world.