The Suez Canal
A vital trading route between the Mediterranean Sea and the Red Sea, the Suez Canal, opened on November 17, 1869. Built by Frenchman Ferdinand de Lesseps using Egyptian forced labour, the canal stretches 192 miles (308 km) long and is 984 ft (300 m) wide at its narrowest point. During its construction, it's estimated that more than 120,000 Egyptians died because of poor conditions and disease.

About 7.5% of world sea trade is carried via the canal today and it costs, on average, around $150,000 per ship to pass through it. The canal has no locks as it's more or less level – the Red Sea is just 1.2 metres higher than the eastern Mediterranean. As a result, many plants and animals from the saltier Red Sea have been found in the Mediterranean causing concern amongst marine biologists.

This image shows sailing ships at the opening ceremony.