Transylvania modern Romania. The plateau is almost entirely surrounded by the Eastern, Southern and Romanian Western branches of the Carpathian Mountains. The area includes the Transylvanian Plain. Other areas to the west and north are widely considered part of Transylvania. In common reference, the Western border of Transylvania has come to be identified with the present Romanian-Hungarian border, settled in the 1920 Treaty of Trianon, though geographically the two are not identical. Ethnographic areas: The area of the historical Voivodeship is . The regions granted to Romania in 1920 covered 23 counties including nearly (102,787–103,093 km in Hungarian sources and 102,200
Celts in Transylvania the River Tisa is depicted in 2nd century BC pottery found at Pecica in Arad County, a prosperous trading center at the confluence of the two peoples. A classic period of Geto-Dacian La Tène culture began in the 1st century BC centered around the city of Sarmizegetusa Regia in south-western Transylvania. Dacian king Burebista defeated the Celtic Boii and Taurisci tribes between 60–59 BC. However, some archaeological finds in Dacian settlements and fortifications feature imported Celtic vessels and others made by Dacian potters imitating Celtic prototypes. These discoveries in sites from regions north and west of Transylvania show that relations