In 72 BCE, the city was seized by the Roman general Marcus Lucullus but was soon restored to Thracian control. In 46 CE, the city was finally incorporated into the Roman Empire by emperor Claudius; it served as the capital of the province of Thrace and gained city status in the late 1st century. Trimontium was an important crossroad for the Roman Empire and was called "the largest and most beautiful of all cities" by Lucian. Although it was not the capital of the Province of Thrace, the city was the largest and most important centre in the province. As such, the city was the seat of the Union of Thracians. In those times, the Via Militaris (or Via Diagonalis), the most important military road in the Balkans, passed through the city. The Roman times were a period of growth and cultural excellence. The ancient ruins tell a story of a vibrant, growing city with numerous public buildings, shrines, baths, theatres, a stadium, and the only developed ancient water supply system in Bulgaria. The city had an advanced water system and sewerage. In 179 a second wall was built to encompass Trimontium which had already extended out of the Three hills into the valley. Many of those are still preserved and can be seen by tourists. Today only a small part of the ancient city has been excavated.