Castra Nemaninga, Ancient Roman fort in Obernburg, Germany.

Castra Nemaninga is the Roman cohort fort of Obernburg, now completely built over beneath the old town. Nothing of its walls stands above ground, but the street layout preserves the plan: Badgasse follows the Via praetoria, the Römerstraße the Via principalis, and the Schmiedgasse the Via decumana. A paving marker in Badgasse shows where the Porta praetoria stood.

A first timber-and-earth fort was built shortly after 100/101 or 100/110 AD, as dated by Egon Schallmayer and Barbara Pferdehirt from the finds. A building inscription from the forecourt of the headquarters building indicates that a stone fort replaced it probably in 162 AD. The site lies on the western bank of the Lower Main, opposite the mouth of the Elsava.

The fort's name survives in local tradition as Castra Nemaninga, and its ground plan still shapes Obernburg's old town: the Badgasse follows the Via praetoria and the Obere Gasse traces the southern front. Since 1984 the site of the Porta praetoria has been marked in the paving of the Badgasse. Most of the rich votive inscriptions come from the sacred precinct of the beneficiarii, the road police stationed about 100 m outside the south wall.

Nothing of the fort stands above ground; its outline survives in Obernburg's street plan. The Badgasse follows the Via praetoria, the Römerstraße the Via principalis, the Schmiedgasse the Via decumana and the Obere Gasse the south front. Since 1984 the Porta praetoria is marked in the Badgasse pavement, so the circuit can be walked through the old town.

In 1849 Major Maximilian Ney had soldiers dig along the road near today's district court, recovering many Roman vessels that seemed to come from graves. Sent to Nuremberg's Germanic National Museum, they were filed under "Oberndorf" by mistake and only correctly assigned to Obernburg in 1968.