The Jews were smuggled and transported out of Denmark over the Øresund strait from Zealand to Sweden—a passage of varying time depending on the specific route and the weather, but averaging under an hour on the choppy winter sea. Some were transported in large fishing boats of up to 20 tons, but others were carried to freedom in rowboats or kayaks. The ketch "Albatros" was one of the ships used to smuggle Jews to Sweden. Some refugees were smuggled inside freight rail cars on the regular ferries between Denmark and Sweden, this route being suited for the very young or old who were too weak to endure a rough sea passage. Danish Resistance Movement operatives had broken into empty freight cars sealed by the Germans after inspection, helped refugees onto the cars, and then resealed the cars with forged or stolen German seals to forestall further inspection.