How do I complete the Blue Tower in Big Walk?

Bring five challenge rewards back to the Blue Tower, take the released Blue Key through all five cutters in order, then place the finished key at the Train plinth.

How many rewards does the Blue Tower need?

Five. The tower counts the rewards returned, not which challenges supplied them.

Do I need to complete every Blue Area puzzle?

No. Blue progression needs five returned rewards and the five cutters. The rest of the area is exploration and completion content.

Where does the Blue Key go?

Through all five cutters, then into the Train plinth.

Why is the Train not moving after I placed the Blue Key?

The Blue route is complete at that point. The Train has an operating state of its own beyond the key placement, so check the Train rather than repeating Blue Tower steps.

What should I do after the Blue Tower?

Blue ends at the Train. From there, pick another major route or let the assistant choose from your saved progress.

Blue Tower route

Big Walk Blue Tower Walkthrough

Return five rewards, release the Blue Key, take it through all five cutters, then use the finished key at the Train.

Blue Tower → 5 cutters
Five ordered cutters
Destination: Train

Blue Tower route

Rewards: 0 / 5 returned
Blue Key: Still locked
Key cutters: 0 / 5 done
Train: Locked

Blue Area challenges0 / 5 complete

Exploration and 100% completion. This is separate from the Blue route above.

Check My Blue Route Show the Blue Tower on Map

Your answers are saved on this device and shared with the Big Key guide, the Train guide and the 100% tracker.

Blue Tower Route at a Glance

One source, five ordered cutters and one destination. The Blue route ends at the Train plinth.

Blue Tube LookoutYou are here
Blue Key released
Cutter 1
Cutter 2
Cutter 3
Cutter 4
Cutter 5
Train

Whether the Train then moves is a separate check, so it is not drawn as the next step on this line.

Votre route bleue

Indiquez où vous en êtes et le prochain objectif bleu reste toujours sous vos yeux.

Where are you in the Blue route?

Pick the line that matches your run. The next Blue objective below follows your answer.

Route status

Blue Key released: ○
0 / 5 cutters: ○

Next Blue objective

Return the rewards the Blue Tower asks for and release the Blue Key.

The Blue Key is still inside the tower. Bring the rewards it asks for first.

Open the Big Key route

Where Is the Blue Tower?

Look for the blue tube-shaped tower standing over the open ground in the middle of the area. That tower is the Blue Tower.

The map below draws the Blue route: the Blue Tower source, its five key cutters and the Train plinth destination, with the Blue Area challenges underneath.

Blue route overlay
Blue Tower source
Five cutters
Train plinth destination
Blue Area challenges

Cutter 1

Cutter 2

Cutter 3

Cutter 4

Cutter 5

Train

Comptage en perspective

Coordonnées

Memory Bombs

Optical Telegraph

Trap Room

Tour bleue

Train

Blue Tube Lookout

The Blue Area around the tower holds its own challenges. Every other landmark sits on the full world map.

Open the Full Interactive Map

Return Five Rewards to the Blue Tower

The Blue Tower has five reward slots. Bring five challenge rewards back to the tower and it releases the Blue Key.

Where: Blue Tube Lookout
What it needs: 5 challenge rewards

Rewards returned

0 / 5 returned

Need 5 more rewards.

The tower counts rewards, not challenge names, so any five valid rewards you carry back will do.

Solving a challenge and carrying its reward back are two separate marks. The slots fill from rewards you returned, not from solved challenges.

Show the Blue Tower on Map

Need Another Reward?

These are the closest challenges you have not cleared yet. Clear one, carry its reward back, and another slot fills.

Take the Blue Key Through Five Cutters

The released key still has to pass through five cutters, in order. Bring the current Blue Key to each one.

Cutter 1
Next
Location
Blue route · cutter 1
What to do
Bring the current Blue Key here.
After this
Cutter 2
Cutter 2
Not complete
Location
Blue route · cutter 2
What to do
Bring the current Blue Key here.
After this
Cutter 3
Cutter 3
Not complete
Location
Blue route · cutter 3
What to do
Bring the current Blue Key here.
After this
Cutter 4
Cutter 4
Not complete
Location
Blue route · cutter 4
What to do
Bring the current Blue Key here.
After this
Cutter 5
Cutter 5
Not complete
Location
Blue route · cutter 5
What to do
Bring the current Blue Key here.
After this
The Train plinth

The cutters are ordered. A key that skipped one is not in its finished state, which is the usual reason the Train plinth stays dead.

Take the Finished Blue Key to the Train

The Blue route ends at the Train plinth. Place the finished key there and the Train gets one step closer to running.

5 cutters complete
Finished Blue Key
Train plinth
Train running

What does the Blue Tower unlock?

• The Blue Tower route unlocks the island Train system.
• The finished key activates the Train plinth, which is how the Train becomes available at all.

Train:: Locked

The Blue route does not open the Chairlift, the Tunnels or the Map Room.

Fix the Train

Is the Train moving?

The key is at the plinth, so the Blue route is done. This last answer decides what you look at next.

Related achievement: Big Ride

Big Ride comes from boarding and riding the Train, not from unlocking it.

Open Big Ride Guide

Why Is the Train Locked or Still Stopped?

Work down the list. The first answer that matches your state is the thing that is still open.

The Blue Key was never released: The Blue Tower still wants its five rewards. Bring them back before looking at cutters. Rapporter cinq récompenses
I have the Blue Key, so where next?: Go to the first cutter that is not complete on the Blue route. The route stays on that cutter until it is done. Trouver ma prochaine découpeuse
I finished all five cutters: The key is finished now. Carry it to the Train plinth and place it there. Destination : socle du train
The key is at the plinth and the Train still will not move: This is no longer a Blue Tower problem. The Train has its own activation state to check, so continue with the Train guide. Le train ne fonctionne pas ?

Stuck on a Blue Area Puzzle?

Match what you are looking at to the challenge, then open the guide that solves it.

I found a number clue instead of a normal puzzle: Open Coordonnées Where does the number point?Solved
I see signals or tiles and cannot read the sequence: Open Optical Telegraph Open Peg Tile SolverSolved
I have to remember a sequence and keep failing it: Open Memory BombsSolved
We keep getting caught crossing the same room: Open Trap Room Open Peg Tile SolverSolved
We have to agree on one count from a viewpoint: Open Comptage en perspectiveSolved

What Comes After the Blue Tower?

Once the Train is running, the Blue Tower route is complete.

The other major routes run side by side. Pick the system you want next, or let the progression assistant choose from your saved state.

Find My Next Objective Big Walk Walkthrough

No coloured tower has to come before another one, so nothing needs the Blue route finished first.

Blue Tower Questions

How do I complete the Blue Tower in Big Walk?: Bring five challenge rewards back to the Blue Tower, take the released Blue Key through all five cutters in order, then place the finished key at the Train plinth. Le parcours en un coup d’œil
What does the Blue Tower unlock?: The Train system. The finished Blue Key activates the Train plinth, and the Train is what the Blue route exists to open. Apporter la clé terminée au train
How many rewards does the Blue Tower need?: Five. The tower counts the rewards returned, not which challenges supplied them. Rapporter cinq récompenses
Do I need to complete every Blue Area puzzle?: No. Blue progression needs five returned rewards and the five cutters. The rest of the area is exploration and completion content. Défis de la Zone bleue
Where does the Blue Key go?: Through all five cutters, then into the Train plinth. Destination : socle du train
Why is the Train not moving after I placed the Blue Key?: The Blue route is complete at that point. The Train has an operating state of its own beyond the key placement, so check the Train rather than repeating Blue Tower steps. Le train ne fonctionne pas ?
What should I do after the Blue Tower?: Blue ends at the Train. From there, pick another major route or let the assistant choose from your saved progress. Outil « Et maintenant ? »

Keep going: Big Walk Walkthrough →

Related Guides

Blue route shape and cutter order last checked on 30 September 2026.