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
Disembark from the church
Finish Following Portents
"Beat" Half-Life in record time.
Survive the gonarch
Heroically listen to the entirety of the Following Portents commentary
Find the kidnapped children
Discover Operation Exodus
Escape the antlion horde... on horseback!
Reunite old foes
Check-in at the Franklin Motel