In a green park beside the River Charente in Rochefort is the Royal Ropeworks. The magnificent building, 374 m long, was built in 1666 for the navy of King Louis XIV. It was part of the Royal Arsenal, alongside stores, a foundry, forges, a gunpowder magazine and dry docks. The navy needed high-quality rope in large quantities. The building shows plain stone walls on the city side but has expensive architectural decoration facing the river. In 1985, the South Wing became an interpretation centre for the sea. The main part of the ropeworks was renovated in 2017. The museum explains the importance of rope in the navy, how the hemp plant was made into yarn and how strands of yarn were twisted together along 300m of the building to make rope. Demonstrations of ropemaking can be seen and visitors can learn how to tie specialist knots. Nearby, the residence of the naval commanders houses a branch of the National Marine Museum.