The three SSM launch complexes were arbitrarily designated by US intelligence as the "A", "B" and and "C" complex. As of early 1963 the "A" complex appeared to be completed and operational. This complex contains two large concrete pads suitable for firing ballistiamissiles served by paved loop-access roads, a control bunker and a drive-through check-out building. Discoloration of the southern pad as well as the possible presence of launching and mobile servicing equipment indicated that firings had occurred. As of early 1963 the other ped appeared to be very clean, but it could also have been used for firings. The two pads under construction at launch complex "B" strongly resemble those at complex "A". Excavation for the pads had been completed by 1963, but construction appeared to have been suspended. Launch complex "C" has one pad and a drive-tbrough building. Construction work appeared to be nearly complete by 1963, and the launch pad could have been used by that time. The ranges of the missile systems to be tested from these facilities cannot be determined from US overhead photography.The launch sites are oriented towards the west and the down-range instrumentation isalso in that direction. The desert terrain to the west allows the firing of surface-to-surface missiles to ranges of up to 1,100nm within Chinese territory. The pads, associated revetments, and supportareas in launch complex "A" closely resemble Soviet facilities at Kapustin Yar used for 700, and probably for 1.,000 n.m. ballistic missiles. launch complex "C" bears resemblance to other Soviet cruise missile launching facilities at Kapustin Yar. The two surface-to-air missile launch sites also resemble SA-2 launch facilities at Kapustin-Yar. The support facilities are also built on the Soviet model. The size of the missile rangehead at Shuang-cheng-tzu connoted a very large program. The facilities available at the test center were sufficient to provide a considerable physical capability to carry out extensive missile research and development programs and some troop training. Housing appeared adequate for at least 20,000 people. The Soviets probably provided technical assistance at least through mid-1960, and early firings probably involved missiles of Soviet manufacture. A successful test launch of the DF-1 (CSS-1) medium range ballistic missile was made in 1966. In April 1970, the DFH-1 satellite was successfully launched aboard the Long March-1 rocket, an improved version of the DF-3 (CSS-2), making China the fifth nation to put a satellite into space, after the Soviet Union, the US, France and Japan. The Jiuquan Satellite Launch Center is used for low altitude posigrade missions with inclinations of 40 degrees or more. All CZ-2C and CZ-2D launches originate at Jiuquan.