Fort Casimir: A Yellowing Bone of Delaware's 1600s Squabble

On a crumbling barrier island, at the very end of Chestnut Street in New Castle, Delaware, Fort Casimir, the Dutch trinket, embodies the Delaware River's century-long argument. Initially, the Dutch claimed the river as their southern border for New Netherland. But in 1638, they gave it to the Swedes. Peter Stuyvesant made another attempt to reclaim it in 1647, but to no avail. It wasn't until after he'd been given the boot that construction on the fort began. Though, the fort bore a short Swedish name, Fort Trinity, before it was the Dutch's once again. The Delaware Valley was a hodgepodge of residents - Swedes, Finns, the Dutch, and French-speaking Walloons, forming the New Sweden colony, still technically under the Deutsch Empire.

Sources: Wikipedia, OpenStreetMap, Wikidata, Wikimedia Commons