One Big Crossword Puzzle

If you are a fan of crossword puzzles, this is one puzzle you will definitely want to try solve. Painted atop the entire external wall of a residential building in the city of Lvov, Ukraine, the puzzle is 100ft tall.

The best part is that unlike normal crossword puzzles, the clues to this 19 square (across) by 34 square (down) brain-teaser are scattered all over the city.

Residents and visitors are encouraged to spend their days exploring the city's parks, fountains, theaters and other landmarks to seek out the clues and try and figure out the answers.

To see if they are correct, they have to return to the building at night, when the empty squares are lit up with fluorescent letters that solve the entire puzzle.

However, before you book your flight to Ukraine, bear in mind that the clues and the entire crossword uses the Cyrillic (Ukrainian) alphabet, which is a little different from the normal English alphabet, making the puzzle a tad bit more difficult to solve if you don't know the language.