restaurants, lofts, and office space. Convention – Includes the George R. Brown Convention Center, Discovery Green, the Toyota Center, and some of the largest hotels in the city. Civic Center – Contains the core of Houston's government, including City Hall – the Houston Public Library Central Library is also here, Harris County – The district includes the Harris County courts complex, and the University of Houston–Downtown is on the edge of the district. Historic – This was the original town center of Houston and dates from the 19th century. The center of the historic district is the Market Square, where the original city hall building stood. Medical – located along Interstate 45 in the southern corner of the district; includes St. Joseph Medical Center, residential properties and the Sacred Heart Co-Cathedral campus. Shopping – Main Street Square has a pavilion and fountains built around the Main Street Square Station – GreenStreet and the Shops at Houston Center are in the area. Skyline – Includes many skyscrapers and forms the base of Downtown's employment. The buildings are connected by the extensive tunnel network. Theater – The 17 block area includes many performing arts venues, Bayou Place, and the Houston Aquarium. Warehouse – Home to Houston's alternative art scene, unique dining options, live music, artists’ studios and downtown's first lofts. History Downtown Houston encompasses the original townsite of Houston. After the Texas Revolution, two New York real estate investors, John Kirby Allen and Augustus Chapman Allen, purchased of land from Thomas F.L. Parrot and his wife, Elizabeth (John Austin's widow), for US$9,428 (). The Allen brothers settled at the confluence of White Oak and Buffalo bayous, a spot now known as Allen's Landing. A team of three surveyors, including Gail Borden, Jr. (best known for inventing condensed milk) and Moses Lapham, platted a 62-square-block townsite in the fall of 1836, each block approximately 250 by 250 feet, or in size. The grid plan was designed to conform to the winding route of Buffalo Bayou; east–west streets were aligned at an angle of north 55º west, while north–south streets were at an angle of south 35º west. Each block was subdivided into 12 lots – five 50-by-100 foot lots on each side of the block, and two 50-by-125 foot lots between the rows of five. The Allen brothers, motivated by their vision for urban civic life, specified wide streets to easily accommodate commercial