Qaen
| Qaen Persian: قاین | |
|---|---|
| City | |
| The mountain city of Qain from above | |
| Nickname: The mountain city of Qayen from above | |
| Coordinates: 33°44′00″N 59°10′52″E / 33.73333°N 59.18111°E | |
| Country | Iran | 
| Province | South Khorasan | 
| County | Qaen | 
| District | Central | 
| Population  (2016) | |
|  • Total | 42,323 | 
| Time zone | UTC+3:30 (IRST) | 
Qaen (Persian: قائن) is a city in the Central District of Qaen County, South Khorasan province, Iran, and serves as capital of both the county and the district.
One of the first Paleolithic signs was discovered in a village called Khonik in the city of Qain. (qayen or Ghayen)