Stockholm has a large public-works project underway: Citybanan. The goal is to excavate a new railroad tunnel underneath the central city, bypassing the antiquated 19th-century track designs which are causing traffic bottlenecks. But the digging underneath the Riddarfjärd bay ended up uncovering a much older form of transport: a sunken ship dating from the fourteenth century.

According to Swedish news articles, the boat was old even when it sank -- the hull had been repaired with a leather patch at least once. Here's as view of the rough location where it sank: