Its arched door from the Roman period is the same as the İstanbul Gate, another city gate of İznik from the Roman period, with its dimensions and construction features. There are inscriptions of Plancius and Hadrian on both the inner and outer sides of the architrave and the frieze. 

There is a courtyard system that is fortified with two round towers at both the Lefke Gate and the Istanbul Gate.

The Turkish fountain, built next to the door, used to transfer water brought by aqueducts from a source about 800m east, which has been used since Roman times.