- http://sacred-destinations.com germany/trier-porta-nigraThe Porta Nigra is the only one of four Roman gates that still stands in Trier; the others were gradually pillaged for their stone and iron.
- spottinghistory.com view/3785/porta-nigra/In 1986 the Porta Nigra was designated a World Heritage Site, along with other Roman monuments in Trier and its surroundings.
- atlasobscura.com places/porta-nigraBuilt in grey sandstone just before the year 200, Trier’s Porta Nigra represents the last bastion of the Roman Empire’s presence north of the Alps.
- http://galenfrysinger.com germany_trier_porta_nigra.htmIn 1986, the Porta Nigra was designated a World Heritage Site, along with other Roman monuments in Trier and its surroundings.
- en.advisor.travel poi/Porta-Nigra-3282In 1986, the Porta Nigra was designated a World Heritage Site, along with other Roman monuments in Trier and its surroundings.
- booked.net visit/attraction/germany/trier-18274/…Porta Nigra served as a main entrance to the Roman city of Trier, which was once one of the largest and most important cities in the Roman Empire.
- youtube.com watch4 bin görüntülemeYayınlandı30 May 2017
- geomerid.com en/place/porta-nigra-trier-travel-…After his death in 1035, he was canonized, and the Church of Simeon of Trier was built based on the construction of the Porta Nigra.
- germany-places.com places/porta-nigra-54290-trierPorta Nigra is a Historical place located in 54290 Trier. It is one of the 264 Historical places in Germany.
- worldtravelimages.net Trier_Portanigra.phpPorta Nigra (Black Gate), an impressive large dark gate built by the Romans as main gate throught the city wall. This is the gate to Trier's Old Town and...