Marstal started out as a natural harbour on the east coast of the island of Ærø. In 1514, it was described as a fishing village – the seeds of the successful shipping town that later grew. Marstal's shipping industry dates back to 1634, when it became possible to dodge Ærøskøbing's trading monopoly on the island. The town's location, beside one of Denmark's main shipping routes – the channel between kingdom and duchies – ensured a good tail wind for the shipping industry. By 1900 or so, this had culminated in a Danish registered fleet of more than 300 cargo ships and no fewer than eight shipyards in the harbour.
Denmark is a seafaring nation, and Marstal on the island of Ærø was once one of its foremost maritime centres. The local economy was founded on the sea, and the islanders have a tradition for contact with other nationalities. In the days of sail, both vessels and seamen from Marstal often sailed on Newfoundland, shipping salt cod from the Canadian province to countries like Spain, Greece, Italy and notably Portugal. This brought them into close contact with the inhabitants of these countries. From the 1890s up until the Second World War, no fewer than 110 Marstal schooners did the "Newfoundland run". Some of them have survived, including the "Bonavista". The winter of 1925-1926 was extremely harsh and five of the Marstal fleet's Newfoundland schooners were lost at sea, three of them without a trace. The Bonavista was a seasoned vessel of the Newfoundland run, but that winter she was caught off the Canadian coast in rough seas along with another Marstal schooner, Svalen ("the Swallow") which was wrecked on some rocks. It took a full 28 days before the Bonavista and her crew of five were brought safely to port, to the great relief of the families back home on Ærø. In 2000, the schooner was incorporated in the Danish maritime cultural heritage under the National Museum of Denmark. She is currently undergoing full restoration at a shipyard at the Marstal Maritime Museum.