The Imperial Cipher — Decode the Habsburg Crown's Secret
Decipher the hidden codes embedded in the Imperial Treasury's most guarded artifacts. Uncover the cryptographic system Maria Theresa used to protect the Pragmatic Sanction and expose a centuries-old Habsburg conspiracy.
📱 1 to 10 phones · 1 team per phone · Independent codes
In 1740, Empress Maria Theresa ascended to the Austrian throne under the Pragmatic Sanction—a decree that allowed female succession, unprecedented in the Holy Roman Empire
The Imperial Cipher — Decode the Habsburg Crown's Secret
You are Emperor Franz Joseph I's secret archivist, tasked in 1897 with finding the encrypted testament of Rudolf I of Habsburg, hidden since 1291 in Vienna's
Decipher the secret codes carved in stone by six centuries of Habsburg rule, from the medieval Hofburg to the catacombs of Saint Stephen's.
How does it work?
Explore the city on foot solving puzzles based on real historical facts. No locked room — the city is your playground.
No app to download. Play directly from your browser. Guided step by step, at your own pace.
One purchase per phone is enough. Play with family, friends or as a couple — everyone participates.
Point your phone at the façade: a historical character appears and speaks to you in your language. Golden letters magically write themselves on the wall to reveal the puzzle answer.
Stuck? Progressive personalised hints. The character repeats the puzzle on demand — at your own pace.
French, English, German, Spanish, Italian + 27 other languages auto-translated by AI.
Want to go deeper?
Places tied to your adventure — optional entries, totally up to you · per person
« Austria est imperare orbi universo »— Official motto of the House of Habsburg (13th-20th centuries), interpreted as 'Austria is to rule the whole world'
The story that haunts this land
Your investigation begins at Michaelerplatz, main entrance to the Hofburg built in the 13th century as Rudolf I's medieval castle courtyard. Before you, the concave facade of the Michaelertrakt designed by Joseph Emanuel Fischer von Erlach extends 120 meters, completed in 1893 under Franz Joseph. The two equestrian Warrior fountains erected in 1897 flank this square where the dynastic motto still resonates. Saint Michael's Church overlooking the ensemble dates from 1220, rebuilt in baroque style in the 18th century. Your phone reveals the first clue carved in the imperial coat of arms: a numerical sequence linked to the palace's 2,897 rooms according to official archives.
Heldenplatz welcomes you with its 70,000 m² created in 1860 as an esplanade before the Hofburg. The equestrian monuments of Archduke Charles of Austria and Prince Eugene of Savoy, sculpted by Anton Dominik Fernkorn in 1860 and 1865, guard the secrets of Habsburg military victories. This square, witness to the speeches of March 15, 1938 during the Anschluss, hides in its cobblestones the second fragment of the Imperial Cipher. Your app reveals ghosts of Austrian soldiers marching between the statues, bearing a coded message linked to the imperial palace's 19 inner courtyards.
The baroque Pestsäule confronts you with Vienna's most mysterious monument, erected between 1682 and 1693 by Emperor Leopold I in thanksgiving for the end of the Great Plague. Standing 21 meters high with its Bohemian black granite base, this column sculpted by Matthias Steinl and Paul Strudel represents the Trinity at its summit. The original Latin inscription 'Auspice Leopoldo Magno Caesare Augusto' conceals a numerical code that your phone deciphers in augmented reality. The 10,000 victims of the 1679 plague rest in Saint Stephen's catacombs, your imperial quest's next stop.
The Österreichische Nationalbibliothek, founded in 1526 by Ferdinand I as the Hofbibliothek, holds the Habsburgs' secret archives in its 80-meter Prunksaal. This hall built between 1723 and 1735 by Fischer von Erlach houses 12.4 million documents, including the Codex Vindobonensis and Charlemagne's 9th-century Evangeliary. Among the 30,000 medieval manuscripts hides Rudolf I's encrypted testament you seek. Your app projects luminous parchments onto the shelves, revealing the Imperial Cipher's final sequence carved in the golden bindings of the imperial collection.
Your mission concludes with the dynastic secret's revelation: the reconstructed Imperial Cipher reveals that the Habsburg Crown never left Vienna, but rests in the Marble Staircase of the Reichskanzleitrakt, built in 1730 for state ceremonies. You take from this journey through imperial Vienna an understanding of the architectural codes that shaped six centuries of European power, from the motto 'Austria est imperare orbi universo' carved in every stone to the 18 monumental staircases that still structure Austria's heart today.
The Route
5-10 curated sites across the territory
The gameplay: AR, camera, hidden clues
At each stop, open your phone camera: an augmented reality character appears on the façade and speaks your language. Hunt the clue — it materializes as golden letters on the real wall or floats in front of you. When you find it, the phone vibrates, an AR chest opens and reveals your answer fragment. 8 stops, 8 clues to find with the camera, 1 final code.
The stops on your route are a surprise. You'll discover them one by one, guided by your phone, starting from the meeting point.
How does it work with a group?
One phone = one team. Pick the number at checkout (1 to 10).
Solo, or a group sharing the screen. One team, one code.
Family, couple, or 2-3 teams competing. Each phone has its own code and its own score.
Friends, bachelor/bachelorette, small office outing — each their own code, each plays at their own pace. Tiered pricing then €6 flat per phone from the 6th.
- ✓All codes are independent — play at the same time OR separately, each team advances at its own pace.
- ✓Leaderboard between your teams + global game leaderboard — each score appears in the public ranking.
- ✓More than 10 phones or need a personalized quest? Discover custom tours.
Ready to live this adventure?
Get my code · 14,90€No calendar booking. Code sent immediately by email.
🔒 Secure payment · Code in 5 min · Free cancellation
Practical info
Why this route?
Imperial Succession
Dive into the challenges Maria Theresa faced to inherit the Habsburg Crown.
Secret Diplomacy
Unravel an ancient diplomatic plan, designed to thwart the intrigues of European courts.
Defense of the Empire
Reconstruct the crucial elements that helped safeguard Austria's integrity.
The fate of an empire rests on your sagacity.
Decipher Charles VI's secret plan and secure Maria Theresa's succession.
9 features nobody else has
OddballTrip combines gamified play, augmented reality and AI. All our competitors deliver 1 or 2 of these angles. We deliver all 5.
AR treasure chest
A golden chest floats in front of the monument. Tap → opening animation → reveals a secret message.
AR narrator character
Point your phone at the façade: a knight, witch, monk, sailor, detective or ghost appears full-screen and speaks to you in your language with their dedicated ElevenLabs voice (each character has their own unique voice) — your living guide.
Magic golden letters
At the puzzle climax, golden letters magically write themselves on the real wall — that's the puzzle answer. An unforgettable visual effect.
Written + audio narration
Every puzzle available as text AND voice-over: read at your own pace or listen eyes-free while walking. Great in groups and for accessibility.
360° radar + vibration
A mini-radar shows the target even behind you, and the phone vibrates when you aim in the right direction.
Heritage storytelling
Every puzzle weaves in real historical facts (architecture, era, anecdotes). You learn by playing — like a gamified audioguide.
Progressive AI hints
3 levels of AI-generated help: vibe → where to look → answer format. You're never stuck.
AR selfie memento
At the end of the game, capture a selfie with OddballTrip banner + mascot, shareable on Instagram, TikTok.
Zero app to install
PWA technology: open the link, it plays in your browser. Same quality as an app, no App Store hassle.
Frequently asked questions
Q01Do I need to download an app?
No, never. You get a link, you click, it plays in your browser. That's the point of a PWA: same as an app, without the hassle.
Q02Does it work offline?
GPS yes (handled by your phone). Maps yes (tiles cached). AI and hints need an intermittent 4G connection.
Q03How long does a game take?
1 h 30 to 2 h 30 depending on your pace. The timer runs but only for the leaderboard — you play at your own tempo.
Q04What happens if I'm stuck?
You get 3 levels of hints per puzzle (increasing penalty). If truly stuck, you can skip the step (45-min penalty but you keep going).
Q05What's the age range?
From 12 without an adult, from 6 with an adult reading puzzles. Works for families, couples, friend groups, companies.
Q06What if my city isn't in the catalogue?
Pre-register or contact us — we'll email you as soon as your city is live.
Q07What is augmented reality exactly?
Point your phone at the façade: a historical character appears full-screen and speaks to you in your language. At the puzzle climax, golden letters magically write themselves on the real wall — that's your answer. After each puzzle solved, a treasure chest floats in front of you. Seeing is believing.
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Your turn to play
Decipher the secret codes carved in stone by six centuries of Habsburg rule, from the medieval Hofburg to the catacombs of Saint Stephen's.
1 purchase = 1 phone. Play several on the same device.
No calendar booking. Code sent immediately by email.
🔒Secure payment · Code in 5 min · Free cancellation
🪙+24 TripCoins granted with your booking
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