Big Walk Train Unlock — Blue Lighthouse Key and Starting the Train

Published 2026-08-13Updated 2026-09-184 min read

How to unlock Big Walk's train: clear the five blue lighthouse puzzles, shape the key on the cutting machines, and start the red, yellow and green trains from the mountainside station.

The train is Big Walk's rolling shortcut — three colorful carriages looping between regions once you crank them to life. The whole unlock revolves around the blue tower, the lighthouse on the island's east side, and it ends with a key, a mountainside station, and the Big Ride achievement.

The blue lighthouse tower on Big Walk's east side

The blue tower — the island's lighthouse, east side.

Step 1: Reach the blue lighthouse

The lighthouse stands on the eastern side of the island. Two approaches work: head left (east) from the red tower area, or if the chairlift is already running, ride it and hop off near the tower to save the legwork.

Step 2: Solve the five lighthouse puzzles

Environmental puzzles dot the ground around the tower — five in total, each hiding one gourd-shaped blorb. Clear all five and bank the full set. None of them are solo puzzles, so keep the group together.

Step 3: Earn the raw key at the top

Carry your five blorbs up the lighthouse and slot them into the five sockets at the top. The control panel behind you releases the raw key blank — the same uncut lump every tower hands out, and just as unusable until shaped.

A key cutting machine working on the raw key

Five machines stand between the blank and a working key.

Step 4: Run the key through the cutting machines

Follow the ground markers down from the tower: five key-cutting machines ring the lighthouse, each arrow pointing to the next. Pass the blank through every one of them and it comes out as the finished blue key.

Step 5: Start the train at the mountainside station

The train station sits on the mountainside northwest of the lighthouse. Slot the key into the platform console and the line wakes up: red, yellow and green trains begin their loops across the island. Step aboard a moving carriage for the Big Ride achievement.

One detail worth knowing once you are aboard: the onboard lever pauses the train mid-route, handy for hopping off at spots between stations or waiting for a friend to catch up.

Characters gathered at the train station platform

The mountainside platform — key goes in the console.

Riding the train over a bridge on the monorail track

All aboard — the loop covers the whole island.

How the train fits the bigger picture

Experienced trekkers rate the train honestly: it is slow and the timetable is sparse, so treat it as a scenic connector rather than a rush hour service — the tunnels stay the fastest way between regions. The train is one stop on the five-key progression covered in our all achievements guide, and it passes right by several radio transmitter landmarks if you are collecting songs along the way.