Boldt Castle, United States

Turrets and steep red roofs rising over the trees on Heart Island, in the St. Lawrence River's Thousand Islands. George Boldt, proprietor of New York's Waldorf-Astoria, began this Rhineland-style castle around 1900 as a gift for his wife, Louise. The love story is the legend here, and it has a sad turn. Louise died in 1904, work stopped, and Boldt never returned to the island. The shell stood empty for decades until the Thousand Islands Bridge Authority bought it in 1977 for one dollar and began restoring it. It is the closest thing to a European fairytale castle you can reach by tour boat in the United States, open seasonally from spring to fall.