Petersburg, city (1990 pop. 38,386), politically independent and in no county, SE Va., on the Appomattox River; inc. 1850. A port of entry and an important tobacco market, it has industries producing chemicals, pharmaceuticals, furniture, structural steel, lumber, paper goods, and medical equipment. Fort Henry was built there in 1646 on the site of a Native American village. A trading post was then established, and in 1784 three villages—Petersburg, Blandford, and Pocahontas—were combined as Petersburg town. In the Civil War, Petersburg, which guarded the southern approaches to Richmond, was under siege from June 15, 1864, to Apr. 3, 1865. After failing to destroy Lee's army in the Wilderness campaign, Grant slipped unnoticed from Confederate lines at Cold Harbor and moved on the city. Lee, forced to defend Petersburg in order to protect Richmond, entrenched his troops there. On July 30, 1864, Union forces exploded a mine under part of the Confederate works and poured into "The Crater," but were driven out with heavy losses. Grant gradually extended his left flank SW of Petersburg to cut off Lee's supplies from the lower South, and Lee was forced to spread his smaller army over many miles of entrenchments. Sheridan's victory at Five Forks on Apr. 1, 1865, followed by a general assault on the Petersburg lines, finally broke Lee's resistance. Petersburg fell on Apr. 3, 1865. Union forces entered Richmond on the same day, and Lee surrendered the remnants of his army at Appomattox Courthouse one week later. Petersburg National Battlefield (est. 1926) encompasses much of the battle scene; many old earthworks and tunnels are preserved, including "The Crater." Other points of interest include Blandford Cemetery, with 30,000 Confederate dead; Blandford Church (1735–37); Center Hill Mansion (1823; now a museum); and Gen. William Mahone's home, now part of the public library. Virginia State Univ. is to the north in the suburb of Ettrick. To the east is Fort Lee, an army quartermaster training center and home of the U.S. Army Women's Museum.