The "Old Town Regensburg with Stadtamhof" has been registered as a historic medieval city on the World Heritage list since 2006 because of the following 3 criteria:

Criterion II:
Regensburg’s architecture reflects the role of the city as a mediaeval trading centre and its influence on the region north of the Alps. Regensburg was an important trading centre on the continental trading routes to Italy, Bohemia, Russia, and Byzantium. In addition, the city had numerous links to the intercontinental silk routes. This enabled an important exchange of cultural and architectural influences to be made which are characteristic of the city’s townscape even today.

Criterion III:
The Regensburg Old Town displays an extraordinary testimony of cultural traditions in the Holy Roman Empire. In the high Middle Ages Regensburg was a favourite meeting place for Imperial Assemblies, but in more recent European history the city also made its contribution as the seat of the Perpetual Imperial Diet from 1663 to 1806. The remains of two royal palaces which date from the 9th century and also the numerous well-preserved historical buildings are evidence of the one-time wealth and the political significance of the city.

Criterion IV:
The Old Town of Regensburg is an excellent example of an inner-European mediaeval trading town whose historical stages of development are well preserved. The development of the trade from the 11th up to the 14th century in particular is illustrated thereby extraordinarily well.