Former Site of Heidenheimer's Castle. In 1857 John S. Sydnor (1812-1869), former Galveston mayor, built the original two-story, eight-room structure at this site. Samson Heidenheimer (1834-1891) bought it in 1884. The German-born Heidenheimer began with a $100 loan and built a fortune as a Confederate blockade runner. He was associated with Sydnor and his son Seabrook in an auction business. Heidenheimer enlarged the house to four stories and 37 room and added castle-like tower and turrets. It changed owners many times after his death; burned in 1973, and was razed in 1975. #7484