The town is renowned for its Roman architecture. Its Roman theatre, the Théâtre antique d'Orange, is described as the most impressive still existing in Europe. The fine Triumphal Arch of Orange, theatre and surroundings were listed in 1981 by UNESCO as a World Heritage Site. At Roman times, Orange was a capital of northern Provence and was regarded as "Miniature Rome".

Old town of Koblenz was always shaped as a triangular - two sides of which are rivers Rhine and Mosel, while the third side was a line of fortifications. This strategic location was appreciated back in 8BC by Romans when they established a military post - thus, citizens celebrated 2000th of anniversary in 1992. Remains of Roman-built bridge can still be found. Most fortifications were gone after 1890 but citadel of Ehrenbreitstein still overlooks the town from another bank of the Rhine. The town is an important centre of the Mosel and Rhenish wine trade.