A full-scale replica of the Spanish-style Japanese-made ship Sant Juan Bautista, commissioned by Date Masamune in 1613 as part of a diplomatic mission to Europe, is on display here (though visitors can no longer go on board due to deterioration of the ship). There's also an an interesting museum with some English signage that tracks the ship's journeys across the Pacific.
Miyagi Sant Juan Bautista Museum
Northern Honshū (Tōhoku)