strait between mainland Denmark (west) and Funen and Ærø islands (east). About 30 miles (48 km) long and 0.5 mile (0.8 km) wide, it is the connection between the Kattegat (an arm of the North Sea) and the Baltic Sea. The strait is deep (50–150 feet 【15–45 metres】) but difficult for large ships to navigate. A railway bridge (1935) and a suspension bridge (1970) cross the Little Belt.