| Ciasne | |
| Settlement Type: | Village |
| Total Type: | |
| Subdivision Type: | Country |
| Subdivision Type1: | Voivodeship |
| Subdivision Name1: | Podlaskie |
| Subdivision Type2: | County |
| Subdivision Name2: | Białystok |
| Subdivision Type3: | Gmina |
| Subdivision Name3: | Supraśl |
| Coordinates: | 53.1833°N 41°W |
| Pushpin Map: | Poland |
| Pushpin Label Position: | bottom |
| Population Total: | 300 |
| Population Footnotes: | (approx.) |
Ciasne is a village in the administrative district of Gmina Supraśl, within Białystok County, Podlaskie Voivodeship, in north-eastern Poland.[1] It lies approximately 5km (03miles) south-west of Supraśl and 120NaN0 north-east of the regional capital Białystok.