Riedenburg is a district of Salzburg and some parts of it belong the historic city centre (Altstadt), even though not to the administrative district of that name. Historically, Riedenburg is even the oldest part of the city: The Rainberg hill, which can be found at its heart, was the site of a Neolithic settlement since 4500 B.C. Later, a Celtic town developed here with wooden fortifications, streets and many houses. Today, nothing of this can be seen anymore - the Rainberg is a nature reserve and not even accessible (at least not officially, that is).
Riedenburg is linked with the main part of the Altstadt through the Neutor, the oldest traffic tunnel of Austria (built between 1764 and 1766). It is therefore popular with hotels: A quiet district that is still very central. The main attraction of Riedenburg is Schloss Leopoldskron with the associated small lake. But let us say a few words on the borders of this district first.
Outlay of Riedenburg
Schloss Leopoldskron marks the southern border; the eastern border are the cliffs of the Mönchsberg hill. Beyond the northern border, you find the district of Mülln, westwards Maxglan. In total, there are only some 7.000 people who call Riedenburg their home. Much of the district was developed after land (former swamps that were gradually drained in the centuries before) was sold in 1880. Therefore, you can find a high number of Historicist Gründerzeit villas. The construction of streets and sewage systems was properly tackled only in 1905. Some ten years later, a tram line connected Riedenburg with the Altstadt.
Note that the Almkanal runs through Riedenburg; the Mülln part of the canal branches off in Riedenburg. For a long time, Riedenburg was associated mainly with two things: The Ofenlochwirtshaus, an inn that was opened in 1670; and the Sternbrauerei, a brewery that still runs a well-known inn at the Getreidegasse. Today, it is mainly regarded to be an expensive and exclusive residential area.
Hidden Treasures of Salzburg
District Riedenburg on the German Wikipedia
City of Salzburg, Official Website