Here is the full list of all 12 Tiny Rails achievements.
Upgrade 50 cars of any rarity.
Upgrade 100 Stations.
Earn 1,000,000 gold.
Purchase 75 train stat upgrades.
Visit 250 Stations.
Collect 45 train cars of any rarity.
Buy 400 cargo items from Markets.
Take 1,000 Passengers to their destinations.
Take 250 VIP Passengers to their destinations.
Collect 30 rare train cars.
Earn 25,000 gold by selling cargo at Markets.
Travel 1,000,000 km/622,000 miles.