Terminous owes its founding to a water-rail connection point, located at the confluence of Potato Slough and the Mokelumne River.  The town earned its name, as it was the “end of the road” into the Delta. It was an especially important trans-shipment point for asparagus from Bouldin Island where the first test fields of the crop were planted.  The town became the focus of vegetables brought in on barges from a wide area for washing, trimming and crating.  At the height of the season, it is estimated that 350 laborers were on hand to process the region’s agricultural bounty with a majority of workers living in Terminous’s “box car city,” made up of de-wheeled wooden box cars set up on old railroad ties.

By the late 1930s, the introduction of refrigerated trucks and smaller packing sheds distributed throughout the area made the town’s freight business obsolete, so Terminous transitioned to recreation and tourism. Many of the original waterfront warehouses have been recycled into boat storage facilities, and the Box Car City is now a mobile home park, camping sites and a large marina.