Mecca's Timekeeper: Abraj Al-Bait Clock Tower (#4)

The 601-meter Abraj Al-Bait Clock Tower in Mecca, Saudi Arabia, isn't just the fourth tallest building; it holds the record for the world's largest clock face. Each of its four clock faces is 43 meters in diameter, illuminated by millions of LEDs and visible up to 30 kilometers away. The complex also provides extensive accommodation for pilgrims visiting the Grand Mosque.