Of the seven hills of Rome, Palantine Hill is in the middle, surrounded by the others. Archeologists have unearthed items dating back to 1000 BC. Many of the rich and powerful Romans of the Republic (509-44 BC) resided in Pallantium before it was merged into Rome. Augustus built his palace here at the start of the empire, setting a precedence for subsequent emperors who also built palaces here (including Nero's palace that burnt to the ground). In the 4th century BC, the Servian Wall was erected as a defensive barrier encompassing the seven hills. The Servian Wall was 11 Km (6.8 miles) long and up to 10 m (33 ft) high. When Rome's population outgrew the area in the 3rd century AD, Emperor Aurelian erected the Aurelian Walls to widen Rome's defense (see Ancient Roman Structures).
