Alderney is the third largest of the Channel Islands. It is 3 miles (5 km) long and 1 1⁄2 miles (2.4 km) wide. Alderney has its own currency which must be the same as the United Kingdom. Alderney coins are widely available to coin collectors however they are not in general circulation. Commemorative coins of £1, £2 or £5 face value in cupro-nickel, silver or gold have been issued by Alderney since 1989.