On lot 39 of a Leonardtown plat designated about 1728, John Stewart’s “Great House” was built about 1734 and stood until 1960, serving over 225 years under names including the Great House, Thompson's Inn, the Tavern Lot, the Old Tavern Lot, Clarke's Hotel, and the Beacon Building. It housed county agencies, local businesses, and professionals, and also operated at various times as a boarding house, hotel, tavern, billiard room, stage depot, and private residence. In 1802 the Georgetown and Port Tobacco mail stage was extended to Thompson's Inn at Leonardtown. Its proprietor, James Thompson Jr., was the father of eight sons, four of whom fought the British during the War of 1812 and became known as the “Fighting Thompsons.” In 1818 tavern proprietor Philip Greenwell, for a yearly rent of one bottle of Madeira wine paid to Henry G.S. Key, obtained the use of a fifteen-foot strip of land running along and parallel with the lot as a sidewalk. From 1839 until the building’s demise in 1960, the Leonardtown Herald and later the Saint Mary's Beacon were published there, and from 1855 through 1952 three generations of the King family—John Franklin, Francis Vernon, and Aloysius Fenwick—lived there and ran the paper from that location. On April 25, 1905, the Leonardtown telephone exchange opened in the Beacon Building with twenty-five phones on the line. On September 2, 1911, after inspecting the new road from Mechanicsville to Leonardtown, Governor Crothers posed for a photograph in front of the Beacon Building with a team of oxen symbolizing the passing of the ox team in St. Mary's as an essential element of transportation. The St. Mary's County Health Department occupied the second floor of the Beacon Building from 1934 to 1953, and two English yew trees on the lot, once in the structure’s front yard, are thought to have been brought from England and planted during the Colonial period.