From Team Fortress Wiki

This is a list of all 78 Dove locations which were found in official Valve maps during the period leading up to the release of Meet the Medic.

Hydro

Well (CP)

Granary

Dustbowl

Gravel Pit

2Fort

Well (Capture the Flag)

Badlands

Gold Rush

Badwater Basin

Pipeline

Sawmill (King of the Hill)

Nucleus (King of the Hill)

Viaduct

Double Cross

Gorge

Upward

Hightower

Thunder Mountain

DeGroot Keep

5Gorge