Johannisborg Castle (Ruin)

Construction of Johannisborg Castle began on May 3, 1614, under Duke John of Östergötland. Originally conceived as a retirement home for his wife, Maria Elisabet Wasa, the three-story structure with six turrets was built by 700 workers. Following the death of the ducal couple in 1618, the unfinished castle passed to the Swedish Crown. Due to difficult ground conditions, construction was prolonged, and the roof was not completed until 1639. The architect Hans Fleming, who had previously designed the burned-down Norrköpingshus, planned Johannisborg with strong fortifications intended to protect the city from sea attacks. These fortifications formed a five-pointed star, surrounded by a moat, and featured a gate tower facing the city. Queen Christina received the castle in 1654 as an endowment after her abdication and resided there for a time after returning from Central Europe. After her death in 1689, it reverted to the Swedish Crown. By 1719, Johannisborg was so dilapidated that it could not withstand the Russian invasion, leading to the burning of Norrköping. Subsequently, the ruin served as a quarry for the local population to rebuild the city.

Today, only the gate tower and three of the original five fortification points of the former Johannisborg Castle remain. The ruin is publicly accessible, with an inscription on the gate tower commemorating Duke John of Östergötland.