Jackson Island is the last remaining interurban island in the Grand Rapids portion of the Grand River. It has a street address of 301 Market Ave SW and both shares its address with and is owned by Grand Rapids City Works.
Geographic coordinates are 42.959359° N, 85.680506° WLatitude: 42°57′33.692″N
Longitude: 85°40′49.822″W.
Naming
Punk Island is a colloquial name of Jackson Island. This name has been attributed to the past proclivity of punk rockers to use the island as a squat in the summer months.
Picture of Punk Island from the West end of the Amtrak Bridge. The island is on the right.