Photo of the Day

a stone gate in Germany dating from the Roman Empire
October 13, 2012

Porta Nigra, Germany

This Month in Photo of the Day: National Geographic Magazine Features

TRIER, GERMANY
The Porta Nigra, or "black gate," still dominates Trier, Germany. A hundred feet tall, it was built in the second century as part of four miles of walls. Trier was a major city in the late Roman Empire, even serving as a regional capital under several emperors.

See more pictures from the September 2012 feature story "Roman Frontiers."


Take a visual tour of Germany »
See pictures of European cities »

Photograph by Robert Clark, National Geographic

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