Vyroneia (Greek: Βυρώνεια, before 1924: Χατζή Μπεηλίκ - Chatzi Beilik) is a town located in the municipal unit of Petritsi in the northwestern part of Serres regional unit, Greece. It is situated near the Bulgarian border, on the right bank of the river Strymon, south of the Kerkini mountains, and east of the Lake Kerkini. Vyroneia is 4 km west of Neo Petritsi and 12 km northwest of Sidirokastro. It has a station on the railway line from Thessaloniki to Serres. Vyroneia, then known as Hadji-Beylik, was a military base for the Greek army during the Second Balkan War. Vyroneia had 1,134 inhabitants at the 2001 census. Near the train station is the National Aquarium of Vyroneia, the second in Greece after Rhodes.