Castaway Island Preserve is a 311-acre nature park in eastern Jacksonville, Florida that abuts the west bank of the Intracoastal Waterway.

[2] The preserve is surrounded by residential neighborhoods west and south[4] with the historic San Pablo River (intracoastal waterway) to the east.

It was determined that the property contained introduced species, so the project manager applied for and was awarded an $18,000 grant from the Florida Department of Environmental Protection for on-site removal, which was completed.

A state grant from Florida Inland Navigation District (FIND) paid for half of those costs and the paved trails and wooden boardwalks are wheelchair accessible.

[3] Planning, engineering, landscape architecture, construction and grant services were provided by England-Thims & Miller.