Fjallavatn

Infobox_lake
lake_name = Fjallavatn
image_lake = Faroe_stamp_513_vagar_-_fjallavatn.jpg
caption_lake = Stamp FO 513 of Postverk Føroya Issued: 7 February 2005 Artist: Eli Smith
image_bathymetry =
caption_bathymetry =
location = Vágar
coords = coord|62|07|21|N|7|17|57|W|region:FO_type:waterbody_source:dewiki|display=inline,title
type =
inflow =
outflow =
catchment =
basin_countries = Faroe Islands
length =
width =
area = 1.02 km²
depth =
max-depth =
volume =
residence_time =
shore =
elevation =
islands =
cities =

Fjallavatn is the second largest lake in the Faroe Islands. It is situated on the island of Vágar and its size is 1 km².