1) The Indian Ocean is the third-largest ocean and is characterized by its warm waters and diverse marine life.

2) The French Revolution, which began in 1789, marked a major turning point in European history, leading to the overthrow of the monarchy and the rise of republicanism.

3) The world's largest particle accelerator, the Large Hadron Collider, is located near Geneva, Switzerland, and spans a circumference of 17 miles (27 kilometers).

4) The Berlin Conference in 1884-1885 divided Africa among European powers and set the stage for the colonization of the continent.