Roč (Italian: Rozzo) is a village in Istria, north-west Croatia, with a population of only 180 people. It is about 50 km south-east of Trieste, Italy, located on the road Trieste — Koper — Učka Tunnel (B8) — Rijeka. Its other names are Rus (quoted as such in a document of 1064), Ronz and Rozzo. Together with Roč, they all derive from the Celtic name Roz: the related name Roc is very common in wide areas under Celts influence. The Romans called it Castrum Rotium or Rocium.
Roč is considered a town rather than a village due to its rich cultural heritage. The local Church of St. Anthony holds the precious Roč Glagolitic Abecedarium from the 13th century. The first Croatian printed book, the 1483 Missale Romanum Glagolitice, was prepared in Roč by one Juri Žakan.
The town of Roč is declared by the authorities as an important cultural monument, as it has a well preserved city walls from the Middle Ages with two entrances, a Roman lapidarium, a Venetian bombarda cannon and a functional watchtower. Furthermore, it has the church of St. Anton from the 12th, St. Rok from the 14th and St. Bertol from the 15th century, and numerous other smaller artifacts preserved in the ancient buildings.
Seven kilometers from Roč is Hum, with a population of only 22 people often called the smallest town in the world. Along the road from Roč to Hum is Glagolitic avenue, a memorial avenue of ten monuments from the history of the Glagolitic alphabet.