Full list of all 11 Half-Life: A Place in the West achievements. It takes around 0-1 hour to unlock all of the achievements in the base game on Windows.
The base game contains 5 achievements, and there are 2 DLC packs containing 6 achievements.
Finish The Charnel House
Finish Following Portents
Survive the gonarch
Disembark from the church
"Beat" Half-Life in record time.
Heroically listen to the entirety of the Following Portents commentary
Find the kidnapped children
Discover Operation Exodus
Escape the antlion horde... on horseback!
Check-in at the Franklin Motel
Reunite old foes