Diocletian's Palace — The Architect's Forgotten Plan
Uncover the secret blueprint hidden by Diocletian's master architect. Decode clues across the palace ruins to reconstruct the forbidden plan that could rewrite Roman history—before it's lost forever.
📱 1 to 10 phones · 1 team per phone · Independent codes
In 305 AD, Emperor Diocletian retired to his colossal palace in Split, a fortress of intrigue and power
Diocletian's Palace — The Architect's Forgotten Plan
You are an imperial archivist, dispatched to Split in 305 AD, tasked with locating the original blueprint of Emperor Diocletian's retirement residence before his abdication.
Your mission
Dive into the heart of Split, into the depths of an imperial Roman city transformed into a living metropolis, where every stone whispers Diocletian's secrets.
A game, a guided tour and a heritage guide — all in one
You're not just buying an escape game. You're carrying a living guide — historical anecdotes, forgotten legends, key monuments, hidden architecture — unfolding as you go.
At each stop, places ordinary guides miss — secret façades, sculpted crests, alleys steeped in history.
Every riddle is rooted in a real historical fact or local legend. You leave with dozens of stories to tell.
Learn to read buildings — flamboyant Gothic, Baroque, Art Deco — like a real art historian, while having fun.
Walk through the city like a novel's character — every alley becomes a stage, every square a theatre.
A voice walks with you at every step, tells the story of each place, reads clues, adds a cinematic feel.
Keep access to the guide & game for 1 year. Come back any time, share it with friends.
« You will not leave this city the way you entered it. »
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
The story that haunts this land
Your quest for the architect's forgotten plan begins at Porta Aenea, the Bronze Gate, built around 305 AD. This southern entrance to Diocletian's Palace was the emperor's direct access from the Adriatic Sea. By observing its original Roman arch structure, you'll discover the first hidden symbols. From there, you'll proceed to Porta Ferrea, the Iron Gate, dated from the same period, historically reserved for military access. These two gates, remnants of Roman military architecture, mark the entry points of an imperial fortress that would become, in the 7th century, the heart of a fortified city when the Croats settled there.
The Decumanus, the main east-west axis of Diocletian's Palace, will then lead you for about 350 meters, across still-visible Roman-era stone slabs. This thoroughfare, built around 305 AD, connected Porta Aenea to Porta Ferrea. In parallel, the Cardo, the north-south axis, intersected the Decumanus at the Peristyle, dividing the palace into four functional quadrants. These main streets of Split's historic center, corresponding today to Marmontova Street and Papalićeva Street, were the functional skeleton of Diocletian's residence, designed for his retirement between 295 and 305 AD.
The imposing enclosure walls, 5 to 6 meters high and 2 to 2.5 meters thick, delimited the residential and administrative quarters of Diocletian's Palace. These defensive walls, built around 305 AD, protected the emperor and his court. You will explore the eastern and western sections, partially preserved and integrated into Split's medieval structures. They bear witness to the grandeur of this historic monument in Croatia, an exceptional example of Roman military architecture inscribed on the UNESCO World Heritage list in 1979, and you will find clues carved by the builders.
Your exploration will take you underground, into the Cryptoporticus, a subterranean gallery about 160 meters long. Built around 305 AD, it served as a foundation for the Peristyle and a climate-controlled circulation route. As you walk through its barrel vaults of white Brač limestone, you will discover remnants of Latin inscriptions and traces of medieval occupation. This archaeological site offers a unique perspective on ancient Roman engineering and contains elements of Diocletian's plan, who, after his abdication, retired here, refusing to return to power, preferring to cultivate his cabbages.
Finally, you will reach Trg Braće Radić, the Peristyle Square, the beating heart of Diocletian's Palace. This rectangular central courtyard, 50 by 40 meters, surrounded by Corinthian colonnades, was built around 305 AD. It housed Diocletian's mausoleum and the Temple of Jupiter, and remains today the urban focal point of Split. It is here, at the convergence of the Decumanus and the Cardo, that you will piece together the fragments of the Architect's Forgotten Plan, revealing the emperor's complete vision for his retirement in Dalmatia. This themed circuit in Split will have provided an immersive experience at the heart of Split's history.
The Route
8 stages through the city
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 · 12€No calendar booking. Code sent immediately by email.
🔒 Secure payment · Code in 5 min · Free cancellation
Practical info
Why this route?
Ancient Geometry
Decipher the proportions and alignments of Roman builders.
Architectural Blueprint
Assemble fragments of a secret blueprint to locate a hidden treasure.
Roman Engineering
Explore the technical prowess that gave birth to the imperial palace.
The strongest stone is nothing without the blueprint that guides it.
An unknown Roman architect, probably.
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
Dive into the heart of Split, into the depths of an imperial Roman city transformed into a living metropolis, where every stone whispers Diocletian's secrets.
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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