At the turn-of-the-century, George C. Boldt, millionaire proprietor of the world famous Waldorf Astoria, began work on a Rhineland Castle on Heart Island. The grandiose structure was to be a six story, 120 room castle, complete with tunnels, a powerhouse, Italian gardens, a drawbridge, and a dovecote. Work was terminated shortly after. Since 1977, several million dollars have gone to restoration. Accessible by water taxi and boat, it is open for self-guided tours from mid-May through mid-October.