Servian Wall
The Porta Esquilina (or Esquiline Gate) was a gate in the Servian Wall, of which the Arch of Gallienus is extant today. Tradition dates it back to the 6th century BC, when the Servian Wall was said to have been built by the Roman king Servius Tullius. However modern scholarship and evidence from archaeology indicate a date in the fourth century BC. The archway of the gate was rededicated in 262 as the Arch of Gallienus.