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