Full list of all 83 The Oregon Trail achievements worth 1,090 gamerscore.
The base game contains 74 achievements worth 1,000 Gamerscore, and there is 1 DLC pack containing 9 achievements worth 90 Gamerscore.
Reach Independence
Have some supplies stolen
Complete "White Water" with at least 10,000 points
Lose a character to dysentery
Discover all of your party's skills in a single run in "The Oregon Trail"
Complete 1,000 events
Collect 1,000 animals
Complete 75% of Journal Achievements
Complete "Bitter Winter"
Complete "Rendezvous"
Complete "Winter Migration"
Complete "The Nature Trail"
Complete "Oregon or Bust"
Deliver an antique to Oregon
Reach Oregon
Complete Journeys with 3 different wagon types
Cross the Big Blue River without incident
Consume 1,000 pounds of food
Discover Fort Laramie
Discover Fort Hall
Discover Fort Boise
Obtain a score of 15,000 or more
Travel 8,000 total miles
Spend a total of $20,000
Complete 100% of Journeys
Complete 100% of Journal Achievements
Reach Independence Rock on or before July 4
Complete 20 Route Challenges
Win against Beckwourth in "Tall Tales"
Hear Lewis Southworth perform with a full backing band
Have a musician play for the rest of the party at a campsite
Make sure Lewis Southworth keeps all the money from his performance
Complete Chauncey's play without making a single mistake
Have all 10 Dragoon Medallions at once
Reunite the Dragoons
Talk the Gunslinger out of his quest for vengeance
Win all 5 of the Gunslinger's challenges
Win $100 or more in total from the Gunslinger's challenges
Make sure Little Mary gets a doll for her birthday
Help Little Mary carve her name into Independence Rock
Successfully fund Samuel Peppard's wind wagon
Travel 500 miles using a wind wagon
Have a unique encounter while traveling with a wind wagon
Survive Lost Hollow
Successfully complete 5 salvage events in a row
Complete Lost Hollow with more than 80 survivors
Complete Lost Hollow in fewer than 15 days
Catch every trophy fish
Trade away a total of 500 pounds of fish
Catch a Yellowfin Cutthroat Trout
Catch a Paddlefish
Catch a Lake Sturgeon
Catch a Pacific Lamprey
Collect more than 40 gold nuggets on the California Trail
Use Nitro at least 12 times on the California Trail
Have the party activate Gold Fever
Trade 5 or more gold nuggets for supplies
Trade supplies for gold nuggets 3 times on the trail
Arrive at Sutters Mill in California
Sell at least 25 gold nuggets to an Assayer
Get swindled with Fool's Gold twice
Have the wagon break down as a result of a nitro explosion
Have a party member killed by a nitro explosion
Use medicine to heal a Burned character completely
Have a Prospector character make it to California
Listen to John Evans's story
Make a donation to the museum
Become lost while searching for the meteorite
Complete 15 Contracts
Collect 25 Gallery items
Collect 50 Gallery items
Complete your Individual Goal for the week
Help your chosen railroad company claim victory
Leave an epitaph for a character with a custom name
Witness a squonk
Witness a hoop snake
Witness a Flambeau ambler
Witness a filla-ma-loo bird
Arrive at Abilene in Kansas
Reach Abilene with excellent cattle condition
Meet Jesse Chisholm
Cook a cowboy's favorite dish
Have a Cook character make a perfect dish