Pereyaslavets (East Slavic: Переяславец) or Preslavets (Bulgarian: Преславец) was a trade city located near mouths of the Danube. The city's name is derived from that of the Bulgarian capital of the time, Preslav, and means Little Preslav (Medieval Greek: Μικρᾶ Πρεσθλάβα). In Greek it was also known as Presthlavitza (Πρεσθλαβίτζα). Several theories exist regarding the exact location of the city: either at Preslav or in its vicinity in Bulgaria, or at Isaccea, Nufăru, Murighiol or Jurilovca in Romania.
A thriving trade centre of the First Bulgarian Empire, it was captured by Prince Svyatoslav of Kievan Rus in 968 (See Sviatoslav's invasion of Bulgaria). During Svyatoslav's absence from the city following the Siege of Kiev (968), part of the citizens revolted and opened the gate to Bulgarian forces. According to Vasily Tatischev, Svyatoslav's governor Volk managed to escape.