Another of Charleston’s historic mansions available to tour is the Calhoun Mansion, the largest single family residence in the city of Charleston, built in 1876. The grand estate was famed in its day and today is one of America’s castles. Tours take place every hour and a half, beginning at 11 a.m. and ending with the last tour at 5 p.m. Tours last 1.5 hours and come at a hefty fee. No self-guided tours are permitted.