From Stamps of the World
Ada (Serbian Cyrillic: Ада; Hungarian: Ada) is a town and municipality (16,991 inhabitants in 2011) located in the North Banat District of the autonomous province of Vojvodina, Serbia. It is situated near the river Tisa in the geographical region of Bačka. The Ada municipality includes the towns of Ada (the seat) and nearby Mol (Mohol), and the villages of Utrine (Törökfalu), Obornjača (Völgypart-Nagyvölgy) and Sterijino (Valkaisor).
Postmark in Yugoslavia era
Postmarks in Kingdom of Hungary (1867-1918)
Postmark in Austrian Empire Voivodina Province (1853-1867)
The ADA post office opened on 22 December 1853 in the Voivodina province.