1. What unique masonry technique was used by the Incas to build Machu Picchu without mortar?

2. Why were the minarets of the Taj Mahal designed to lean slightly outward?

3. What is the official name of the distinctive orange color used on the Golden Gate Bridge?

4. From which region in Wales were the 'bluestones' of Stonehenge transported?

5. What part of the original colossal lion gate at Sigiriya still exists today?

6. What was the meeting place of the Roman Senate located within the Forum?

7. Mount Fuji is classified as which type of volcano known for its symmetrical, conical shape?

8. What is the most common geometric shape of the basalt columns at the Giant's Causeway?

9. The bronze-colored lattice wrapping the NMAAHC pays tribute to the historic craftsmanship of which group?

10. The design of the Oriental Pearl Tower was inspired by which traditional art form?

11. What lies directly beneath the vault of the Arc de Triomphe?

12. Unlike the Panama Canal, why does the Suez Canal not require a system of locks?

13. What natural barrier made escaping from Alcatraz nearly impossible for inmates?

14. How did the Roman army finally gain access to the fortress of Masada during the siege?

15. The superconducting magnets in the LHC are cooled to a temperature colder than what?

16. What is the name of Bangkok’s most famous temple, known for the Emerald Buddha?

17. What is the traditional Thai greeting called?

18. What is the climate in Bangkok generally classified as?

19. Which Bangkok temple is famous for the Reclining Buddha statue?

20. Which area in Bangkok is famous for vibrant nightlife?