It refers to the period when the most important settlements between Niksar and Amasya, namely Erek, Karayaka, Sonusa (Uluköy), and Taşâbat (Taşova) were collectively named as Nevah-i Erbaa or "four towns" as they were in the same region and close to one another. Even the accrued taxes of the time were recorded in this name. In 1840, the taxes collected from these four towns were registered to be 47,243 kuruş.
The period when the four most important settlements between Niksar and Amasya – Erek, Karayaka, Sonusa (Uluköy), and Taşâbat (Taşova) – were collectively known as Nevah-i Erbaa or "four towns" due to their location in close proximity.