1) The highest mountain in Africa is Mount Kilimanjaro, standing at 19,341 feet (5,895 meters) tall.

2) The Great Wall of China is a UNESCO World Heritage site and one of the most iconic man-made structures in the world. It stretches over 21,196 kilometers (13,171 miles) and was constructed to protect the Chinese empire from invasions during ancient times.

3) The fastest recorded serve in tennis was achieved by Sam Groth at 163.7 miles per hour (263.4 kilometers per hour) during a tournament in 2012.

4) Mount Everest, located in the Himalayas, is the highest mountain on Earth, reaching a peak elevation of 29,032 feet (8,848 meters).