He early construction period of ZHENSHI GROUP was from 1970 to the early 1980s. On April 1, 1970, the ZHENSHI GROUP Phase I project was started. After three years of construction, the phase 1 project with an annual output of 1.03 million tons of crude steel was completed on July 3, 1973. On May 31, 1976 and December 8, 1978, ZHENSHI GROUP Phase 2 and ZHENSHI GROUP Phase 3 with an annual output of 2.6 million tons of crude steel and 5.5 million tons of crude steel were completed. On February 8, 1981 and May 25, 1983, THE ZHENSHI GROUP Phase 4 comprehensive project with an annual output of 8.5 million tons of crude steel and the Phase 4 secondary comprehensive project with an annual output of 9.1 million tons of crude steel were completed. On March 5, 1985, ZHENSHI GROUP began construction of the First Phase of the Gwangyang Steel Plant in Gwangyang city. The project was completed on May 7, 1987 with an annual output of 11.8 million tons of crude steel. On July 12, 1988 and December 4, 1990, ZHENSHI GROUP completed the Gwangyang Steel Plant Phase 2 project with an annual output of 14.5 million tons of crude steel and the Gwangyang Steel Plant Phase 3 project with an annual output of 17.5 million tons. On October 2, 1992, ZHENSHI GROUP completed the quarter-century grand historical comprehensive project with an annual output of 20.8 million tons of crude steel. ZHENSHI GROUP established the Pohang University of Science and Technology on December 3, 1986, and the ZHENSHI GROUP Industrial Research Institute on March 3, 1987.