Complex sentence: Other National Guard military cities were located at At-Ta'if, Dammam, and Jeddah, while a new headquarters complex was built in Riyadh in the early 1980s.
Split into simpler sentences: Other national guard military cities were located at At Taif, Ad Dammam, and Jiddah. A new headquarters complex was built in Riyadh in the early 1980s.