The body of water that separates the UK from continental Europe is the English Channel. This approximately 33.8-kilometer (21-mile) wide channel connects the North Sea to the Atlantic Ocean and serves as a crucial navigational route for maritime traffic. The English Channel is historically significant and has played a role in various military and trade activities. Today, it is well-known for the Eurotunnel, which facilitates rail transport between the UK and mainland Europe, enhancing connectivity and trade.