From 1663 until the dissolution of the Holy Roman Empire in 1806, Regensburg was the seat of the Immerwährender Reichstag — the Perpetual Imperial Diet, the first standing parliament in European history. The Document Reichstag Museum, in the Old Town Hall (Altes Rathaus) where the diet actually met, presents this extraordinary period in Regensburg's history. The original debating chamber and the torture chamber beneath it can both be visited.
The exhibition covers the complicated mechanics of the Empire — how the three "colleges" of electors, princes, and imperial cities voted, how ambassadors negotiated, and how the city managed the permanent presence of dozens of diplomatic delegations. For anyone interested in the roots of European political institutions, this is genuinely significant ground. The building itself, a sequence of medieval halls, is also among the finest civic Gothic architecture in Bavaria.