Ostra was an ancient Roman town near the modern town of Ostra Vetere.

[1] The Roman town was inhabited from the 3rd century BC until the 6th century AD.

[2] Pliny the Elder mentions Ostra with another ancient town, Suasa, 8 kilometres (5 mi) west.

[3] Neither town survived beyond the classical period.

Though Ostra is little mentioned by ancient authors, excavations there have brought to light remains of various buildings and several inscriptions.