4 Best Sights in The Adirondacks and Thousand Islands, New York

George C. Boldt, proprietor of the Waldorf-Astoria Hotel in New York, began building this 120-room Rhineland-style castle on Heart Island for his wife, Louise, in 1900. Four years later, when she died suddenly, he ceased work on the castle. The building remained deserted for 73 years, abused by vandals and weather. Since 1977, millions of dollars have been poured into restoration work. It's worth a trip to the 5-acre island to see the castle. Its fleet of wooden boats is in the Boldt Yacht House, on Wellesley Island. Uncle Sam Boat Tours runs shuttle boats between Alexandria Bay, Heart Island, and Wellesley Island.

Sagamore Lodge and the 26 adjoining buildings that make up Great Camp Sagamore were built in the late 1800s by William West Durant, a prominent Adirondack figure. Designed in a Swiss-chalet style, the lodge was built with native spruce, cedar, and granite, and its rustic style set a precedent among the well-heeled set with retreats in the area. Bought and expanded by the Vanderbilt family in the early 1900s, Sagamore is now owned and run by a nonprofit organization that sponsors meetings, seminars, and classes, and rents rooms by the night or week. Classes and activities include canoeing, rustic furniture making, mosaic twig decoration, and mountain music. Tours (reservations required) take you to a blacksmith shop, furniture shop, icehouse, and livestock buildings, as well as to the main lodge. The camp is about 30 mi southwest of Blue Mountain Lake.

Guides lead 45-minute tours, up and down many stairs, through this lovely turn-of-the-20th-century castle on Dark Island. The castle, originally known as the Towers, was built as a summer home for Frederick G. Bourne, president of the Singer sewing-machine company. Famed American architect Ernest Flagg modeled the four-story, 28-room structure on a Scottish castle, giving it all sorts of interesting nooks and crannies. To get here, take a boat from Alexandria Bay. Empire Boat Lines and Uncle Sam Boat Tours include Singer Castle in their sightseeing cruises.

President Calvin Coolidge used this great camp on Lake Osgood as his "summer White House" in 1926. Although built in 1907 and expanded in 1911 by William Massarene and Addison Mizner, the camp is noted for blending rustic architecture with a rather modern sensibility. If you're not staying at one of the guest cabins here, you may see the camp only as part of a guided tour. The tours (1½ to 2 hours) take in the bowling alley, tennis house, dining and great rooms, boathouse, and guest cabins. A Japanese teahouse on a small island is accessed by an arched stone bridge. The camp is 12 mi northwest of Saranac Lake.