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Vallée de la Loire 2New

The Castle's Secret

A three-century-old mystery resurfaces at Chambord. Follow an alchemist's trail and uncover hidden secrets.

3-4 hours
On-site required
12 puzzles
Medium
The Castle's Secret

Synopsis

In 1723, alchemist Nicolas de Valmont vanishes from Chambord Castle. His final notes hint at a discovery that could "change the course of history". Three centuries later, an encrypted manuscript resurfaces during restoration work.

You are called to solve this historical riddle by exploring the places Nicolas de Valmont used to visit. Each clue brings you closer to the truth about his disappearance—and the nature of his mysterious discovery.

Blending real history and captivating fiction, this chapter immerses you in the 18th century while showcasing the exceptional heritage of the Loire Valley.

What you'll learn

  • The history of alchemy in the Age of Enlightenment
  • Renaissance architecture of Loire castles
  • Symbols and secret codes used at the time
  • Daily life in the 18th century

Exploration area

The investigation takes place within a 5 km radius around Chambord Castle

Main places

Chambord Castle

Starting point of the investigation. Visit the royal apartments and the terrace.

Formal gardens

Explore historic gardens and hidden sculptures.

Royal chapel

Discover religious and alchemical symbols carved into the stone.

Estate forest

Walk the forest trails in search of natural clues.

Important: Access to the castle requires an entry ticket (not included). You can start the investigation even if you haven't bought your ticket yet—some puzzles are accessible from outside.

map of Loire Valley castle region with investigation markers and points of interest, cartographic style

Approximate area

5 km radius

Puzzle preview

Discover 3 examples of puzzles you'll solve (spoiler-free!)

Puzzle 1Text

The Encrypted Manuscript

Decrypt an excerpt from Nicolas de Valmont's journal written in a code used by 18th‑century alchemists. Clues are hidden in the castle frescoes.

15–20 minutes
Puzzle 5QR Code

Hidden Symbols

Find and scan 4 QR codes hidden in different parts of the castle. Each code reveals a fragment of an alchemical formula you'll reassemble.

30–40 minutes
Puzzle 9Photo

Solstice Shadow

At a precise time of day, a sculpture's shadow points to a specific place. Take a photo of the phenomenon to unlock the next clue.

10–15 minutes

Text puzzles

5

Multiple choice

3

QR codes

2

Photos

2

Progression system

How to advance through the investigation and unlock the final solution

Solve puzzles

Each solved puzzle grants a clue. You can solve puzzles in any order, but some become easier after others.

Hint system available

Collect clues

Gather all clues in your journal. The more you collect, the clearer the big picture becomes. You need at least 10 out of 12 clues to access the conclusion.

Auto journal

Solve the mystery

Once all clues are collected, you unlock the final puzzle that reveals what happened to Nicolas de Valmont and the nature of his discovery.

Completion badge

Rewards & unlocks

"Loire Investigator" badge
Access to bonus chapter "The Heirs"
Exclusive historical document (PDF)
Partner discount (castle shop)

What you'll need

Get ready before you start

Smartphone

iOS 14+ or Android 9+

Charged battery

Bring a power bank

Entry ticket

Chambord Castle

Comfortable shoes

About 5 km walking

Recommended

  • Water bottle
  • Notebook & pen
  • Cap/hat
  • Camera (optional)

Best time to play

  • Morning: fewer crowds
  • Spring/autumn: pleasant temperatures
  • Avoid: peak weekends
  • Playable in rain (indoors)

Questions about this chapter

Everything you should know before starting

Do I really need to be there in person?

Yes. This chapter requires your physical presence at Chambord Castle and nearby areas. Several puzzles rely on geolocation check-ins, QR codes to scan onsite, and direct observation of architectural elements.

How long should I plan for?

Plan for 3–4 hours for a full session, but you can split the investigation across multiple visits. Your journal saves progress automatically.

Is the castle accessible for reduced mobility?

The ground floor and gardens are accessible, but some areas needed for all puzzles require stairs. An adapted version is in progress.

Can I play with kids?

Yes—recommended for families with children aged 10+. Younger children can participate with adult guidance.

What if the castle is closed?

The app checks opening hours before you start. In case of an exceptional closure, your chapter is paused and you can resume later without losing progress.

Is there internet connectivity onsite?

The app works offline for puzzles and notes. A connection is only needed for some validations (check-ins, photo uploads), and sync resumes automatically when you're back online.

How difficult are the puzzles?

This chapter is rated medium difficulty. A progressive hint system is available for each puzzle.

Can I replay after finishing?

Yes. You can reset your progress anytime to replay, while keeping your achievements and stats.

What players say

4.8/5

Based on 127 verified reviews

Marie L.

Marie L.

"An amazing way to visit Chambord! The puzzles are clever and made us notice details we'd never have seen otherwise. Perfect for families."

2 weeks ago
Thomas B.

Thomas B.

"Great concept! A few puzzles were challenging, but the hint system helped. The story is engaging and the reality/fiction mix is spot on."

1 month ago
Sophie D.

Sophie D.

"We loved it! Much more than a tourist visit. The investigation gives meaning to exploration and you learn a lot. The final reveal is surprising."

3 weeks ago

Player statistics

3h 24m

Average time

89%

Completion rate

4.2

Hints used

127

Active players