Island No. 1 is a partially submerged island in the Napa River, upstream of San Pablo Bay. It is in Napa and Solano County, California, and parts of it are managed as part of the Napa-Sonoma Marshes Wildlife Area. Its coordinates are 38°08′35″N 122°20′40″W, and the United States Geological Survey measured its elevation as 3 ft (0.91 m) in 1981. It, along with Island No. 2, Green Island and Tubbs Island, are labeled on a 1902 USGS map of the area.
Island No. 1, submerged in March 2023 (as seen from the northern part of an internal levee, looking south).
An aerial view, looking toward the west, of the Napa River where it flows into San Pablo Bay through Vallejo. Islands visible include, from bottom of image: Mare, No. 1, Knight, Russ, No. 2, Green, Bull, Edgerly, Coon, Little, and Tubbs.
Island No. 2 is a mostly-submerged island in Solano County, California. Formerly swampland, it was reclaimed into productive farmland, and became the subject of lengthy legal disputes in the early 20th century. Since then, it has become again submerged, and is now part of the Napa-Sonoma Marshes Wildlife Area.
Panoramic photo of Island No. 2 in March 2023
An aerial view, looking toward the west, of the Napa River where it flows into San Pablo Bay through Vallejo. Islands visible include, from bottom of image: Mare, No. 1, Knight, Russ, No. 2, Green, Bull, Edgerly, Coon, Little, and Tubbs.
Aerial photo of Island No. 2 in 1942