Roman Regensburg

In front of you stands the Porta Praetoria. Together with the Porta Nigra in Trier, it is one of the few surviving Roman gates north of the Alps. This is not a reconstruction, but a remnant of the legionary fortress Castra Regina. The camp was begun under Emperor Marcus Aurelius, when Rome wanted to secure the frontier on the Danube, and was completed in 179 AD. The building inscription also names his co-emperor, Commodus. You can see large limestone blocks and the shortened remains of the gate, now squeezed between the houses on the street called Unter den Schwibbögen, "Under the Arches." This was the north gate of the fortress, the exit toward the Danube and the land north of the river. It faced the frontier, the Limes. In the Middle Ages the Porta Praetoria was built into the Bischofshof, the bishop's palace. That is why it survived, even though the upper part was later altered and much of the structure was taken down. You can still see the eastern flanking tower and one of the two arches. The interior is not accessible from the street; it is opened on the guided tours beneath Niedermünster.

This was the north-east corner of the legionary fortress. In front of the east façade, where St.-Georgen-Platz, St George's Square, meets the street Unter den Schwibbögen, a stretch of the Roman wall is freely accessible. Official city texts name this corner sometimes as St.-Georgen-Platz and sometimes as Hunnenplatz, Huns' Square. They mean the same angle of wall, uncovered in 1905. Castra Regina measured about 540 by 450 metres and had four gates. From here the north wall ran west to the Porta Praetoria, and the east wall ran south to Dachauplatz. Since Roman times the street level has risen, so some remains now stand lower than the wall once rose. Even so, the corner is still easy to read in the street plan. The fortress wall later also enclosed the residence of the Bavarian dukes and the Carolingian kings. On the east side it remained in use for centuries as part of the medieval town wall. We follow that line now, to the south.

Beneath the church of Niedermünster, about six metres below today's street level, lie remains from inside the fortress: traces of soldiers' barracks that were rebuilt more than once. Later layers follow, up to the Romanesque church of the 12th century. From the street you can see none of this. The excavation can be visited only on a guided tour. Public tours run on Sundays, Mondays and public holidays at 2.30 pm, and last about 75 minutes. Tickets are sold at the information centre at Domplatz 5, beside the cathedral. Groups are limited to 15 people. The same tour also opens the otherwise closed interior of the Porta Praetoria. For this walk we stay outside. The place itself is the point: we are in the north-east corner of the camp, just behind the wall. The barracks of the Third Italic Legion, Legio III Italica, stood here. The houses of senior officers lay further west, on the main street of the fortress. We will come to those at the end, on Neupfarrplatz.

In the basement of the car park on Dachauplatz, a long stretch of the east wall of Castra Regina stands in large ashlar blocks, separated from the traffic and free to visit. The information point in the car park closes at night. The wall itself remains freely accessible. It was uncovered in 1971, when the car park was built. The east gate of the fortress, the Porta principalis dextra, stood in this area. In 1873, during construction of the Carmelite brewery on Dachauplatz, its building inscription was found. The stone slab now hangs across the square in the Historisches Museum, the Museum of History, and the city regards it as the founding inscription of Regensburg. The Roman ashlar wall lost its importance on the west side around the year 920, when the town was first enlarged. On the east it remained part of the town wall for about another 400 years, and on the south and south-east until the 19th century. That is why such long sections survive on this side.

The Historisches Museum, the Museum of History, occupies the former Minoritenkloster, a Franciscan monastery, directly opposite the Roman wall in the car park. In the galleries on Roman Regensburg hangs the fortress's building inscription: two fragments of a limestone slab, found in 1873 in the foundations of the east gate. The surviving text names Emperor Marcus Aurelius and his co-emperor Commodus. They had a circuit of walls, gates and towers built for the Third Italic Legion. From the imperial titles, the inscription is dated to the years 179 to 180 AD. The city describes this slab as the only original stone founding inscription of a German city. The museum also shows finds from the 1st to the 5th century and a model of the Porta Praetoria under construction. The museum is open Tuesday to Sunday and on public holidays from 10 am to 4 pm, and closed on Mondays. Admission is 5 euros, and free on the first Sunday of the month. For this walk, a short visit to see the inscription is enough, if the museum is open. Otherwise stay outside and continue to the south-east corner.

In front of us lies a stretch of the south-east fortress wall about 80 metres long, of large limestone blocks, still in its original place. It was uncovered in 1955 and 1961 and later laid out as a walkable monument. Here you do not see a single gateway, but the line of the defences themselves. Castra Regina was completed in 179 AD. It had room for up to 6,000 soldiers of the Third Italic Legion. A ditch lay in front of the wall, and towers stood at regular intervals. When Roman administration ended, the wall did not disappear. It was reused and repaired in the Middle Ages, and on the south and east sides it remained part of the town wall for a long time. On the same square is the Römerrastplatz, the Roman rest area, laid out in 2018: a fountain set flush with the ground, seating blocks made from original Roman ashlars, and a steel plate by the artist Paul Schinner showing the course of the Danube. This is not an ancient building, but a modern place to pause beside the wall. You can stop here briefly before the path turns back into the former camp.

The tower in front of you is called the Römerturm, the Roman Tower, but it is not Roman. The official list of monuments records it as the so-called Römerturm, or Pfalzturm, a palatine tower: a six-storey building of ashlar and rubble stone, put up around 1210, probably on a Carolingian foundation from the second half of the 9th century. The timber interior is dated to 1430 or 1431, the tent roof to 1573 or 1574. Next to it, at Alter Kornmarkt 10, the Old Grain Market, stands the Herzogshof, the ducal court, dating in its core from the late 12th century, the first residence of the Wittelsbach family in Bavaria. Since 1937 a Schwibbogen, a flying arch, has linked the court to the tower. Both belong to the later palatine complex inside the former legionary fortress, in the area between the Alte Kapelle, the Old Chapel, the cathedral and Niedermünster. You will see no Roman masonry on the tower itself. What is Roman here is mainly the place: we are back inside the former enclosure.

Set into the façade of the Romanesque tower house at Salzburger Gasse 1 is a Roman Türstock, a stone door frame, of limestone, no longer in its original position. The official list of monuments dates it to around 179 AD, the building period of the fortress. The house itself is Romanesque, and its core is dated to 1196. A Türstock is the stone frame of a doorway, built in to carry the load. The Romans cut their ashlars precisely for this kind of work. Older descriptions often call the same piece a Türsturz, a lintel. Officially it is recorded as a Türstock. We are standing at the Alter Kornmarkt, the Old Grain Market, inside the former fortress, no longer at the Porta Praetoria. From the great circuit of walls we have come to a single reused building element. Pieces like this came from gates, houses and military buildings of Castra Regina.

About six metres under Neupfarrplatz, the New Parish Square, lies a section of the interior of Castra Regina. Wall lines and remains of a tiled floor were uncovered here. They belonged to a house, rebuilt more than once, on the via principalis, the main street of the fortress, and are interpreted as the residence of a senior officer. From above, none of this is visible. The underground rooms can be visited only on a guided tour. Public tours run on Mondays, Thursdays, Fridays and Saturdays at 2.30 pm, and also on Sundays in July and August, and last about 60 minutes. Tickets and the meeting point are at the Tourist Information in the Altes Rathaus, the Old Town Hall, on Rathausplatz 4. For this walk we stay on the square. Officers' houses stood here, not the barracks we mentioned at Niedermünster. In the later layers lies the medieval Jewish quarter as well; the guided tour presents that in more detail. The main circuit of the walk ends here, in the middle of the city, above the interior of the camp.

The Ostentor, the East Gate, is not Roman. The official list of monuments dates the building to two phases, 1285 and 1385. In front of you stands a five-storey Gothic gate tower of stone, with two smaller octagonal flanking towers on the east side. Two pointed arches lead through into a hall with a ribbed cross vault. Narrow slits remain in the sides; portcullises once hung above, and on the east side there are openings for pouring and shooting. Until 1889 this gate was the only way into the city from the east. Ostengasse, East Lane, follows an older alignment. North of the lane, just before this later gate, a larger bath complex stood in the Roman civilian settlement. Its plan is known from surveys; nothing of the building itself is visible. This additional stretch ends here: from the north gate of the fortress, along the wall and through the camp interior, to the later eastern edge of the medieval town.