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