The Macau Peninsula has a gate built on the northern isthmus, for how long did it serve as a border?
Portas do Cerco The Portas do Cerco is an area in Nossa Senhora de Fátima, Macau, China. Located on the northern tip of the Macau Peninsula, it is known by its border gate separating Macau from mainland China. The gate was built in 1849 to replace a crumbling wall that was erected in 1573 to mark the border of the Portuguese colony. It was the site of the Passaleão Incident, a clash between the Qing dynasty and the Kingdom of Portugal in 1849 over the death of Macau's governor Ferreira do Amaral. Led by Colonel Mesquita, Portugal won the small battle which led to the extension of Macau's border northwards. At the limit of said expansion, the Portas do Cerco was built with the inscription "A pátria honrai, que a pátria vos contempla" (Portuguese for "Honor your motherland, for your motherland looks over you") on the façade on its inner arch in 1849. For the next 155 years, the gate served as the border between Macau and China.
Northern Silk Road The Northern Silk Road is a prehistoric trackway in northern China originating in the early capital of Xi'an and extending north of the Taklamakan Desert to reach the ancient kingdoms of Parthia, Bactria and eventually Persia and Rome. It is the northern-most branch of several Silk Roads providing trade, military movements and cultural exchange between China and the west. The use of this route was expanded pursuant to actions by the Han Dynasty in the latter part of the first millennium BC to push back northern tribes and control the safe passage of Chinese troops and merchants.