is an island in the municipality of Miura, Kanagawa Prefecture, Japan, off the southernmost tip of Miura Peninsula, facing Sagami Bay.
It is home to the JÃ Âgashima Lighthouse, the fourth oldest western style lighthouse to be built in Japan. JÃ Âgashima Park is located on the eastern part of the island.
JÃ Âgashima is connected to the mainland by a box-girder bridge since 1959, which was the longest in Asia in 1963.