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Discover Leiden in 90 minutes with a self-guided walking tour featuring puzzles and historic stops, ideal for families and curious explorers.
Leiden’s 90-minute self-guided walking tour, “The Stolen Keys,” offers a fun and flexible way to explore the city’s most iconic sites. Priced at $22.59 per group (up to 6 people), this tour is designed for those who enjoy combining sightseeing with interactive puzzles. It features a mobile app that guides you through eight historic stops across the city, making it perfect for families, friends, or solo explorers looking for an engaging activity without fixed schedules. With an average booking window of six days in advance, it’s accessible for last-minute plans or well-planned outings.
While this tour allows you to discover Leiden at your own pace, a few reviews highlight areas for improvement, particularly regarding puzzle accuracy and app stability. However, overall, it remains an attractive option for travelers who want to see Leiden’s highlights with a playful twist. The tour’s flexibility, combined with free access to key landmarks, makes it a worthwhile choice, especially if you appreciate self-paced exploration.

The tour begins at Molenmuseum de Valk, an original corn mill from 1743 located in the heart of Leiden. This historic building still stands within the city centre, offering a glimpse into the city’s milling past. Visitors should note that admission to the mill is not included in the tour price, so arriving prepared is wise if you wish to explore the interior.
Standing at this iconic windmill, travelers get their first taste of Leiden’s architectural heritage. The app then guides you toward the next stop, seamlessly blending history with interactive puzzles designed to educate and entertain.
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Next, the route takes you to Doelenpoort, an original city gate that once provided access to the militia training fields protecting Leiden. This landmark is free to visit and offers a tangible connection to the city’s medieval defenses. As you pass through, the puzzles challenge your knowledge of Leiden’s historical security measures and urban development, adding an extra layer of fun to this picturesque site.

The Pieterskerk Leiden stands out as one of the biggest and oldest churches in the city. The tour encourages visitors to investigate this Gothic-style church and its surroundings through engaging questions. While the church itself is free to view externally, the focus remains on understanding its significance in Leiden’s spiritual life and architecture.

The Rapenburg street features prominently in Leiden’s landscape, and the tour guides you across this famous canal. This street’s historic buildings and lively atmosphere make it a favorite among visitors. The puzzles related to this location test knowledge about its role in Leiden’s maritime history, adding a layer of interactivity during your stroll.
The Hooglandse Kerk is another highlight along the route. The tour prompts an exploration of this church’s architecture and surroundings, allowing participants to appreciate its Gothic design and the tranquil atmosphere of its square. The church’s exterior is free to admire, and the puzzles focus on its historical importance within Leiden.
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As you move through the shopping district, the Hartebrugkerk captures attention with its elegant architecture. The tour passes by this church in the midst of commercial activity, providing a contrast between spiritual heritage and urban life. The puzzles challenge visitors to uncover details about its history and role in local community life.
The route then crosses De Burcht, an ancient fort now used as a city park. This site offers panoramic views of Leiden and provides insight into the city’s defensive past. The puzzles here explore the purpose and history of the fortress, making it an educational stop amidst scenic surroundings.

The tour concludes at the Koornbrug, a bridge from 1642-1825 situated in the middle of Leiden’s city centre. This historic crossing serves as a fitting ending point, with the app signaling the close of your exploration. From here, it’s about a 10-minute walk back to the starting location, offering a relaxed way to wrap up your adventure.
The meeting point is at Lammermarkt, in Leiden, with the tour ending at the Koornbrug. The entire experience is self-guided, relying on the discovery app you must download beforehand. The tour is available every day from 9:00 AM to 5:00 PM from September 2022 through June 2026, giving you plenty of flexibility.
Participants should bring their smartphone and internet connection, as these are not included. The activity is designed to accommodate most travelers, and service animals are permitted. The tour is exclusive to your group, offering a private experience without mixed groups.
The duration typically falls between 1 hour 15 minutes and 1 hour 45 minutes, depending on how long you spend at each stop and how quickly you solve the puzzles. The route was reported to take about 1 to 2 hours, making it suitable for a relaxed exploration without feeling rushed.
The puzzles are designed to be fun and educational, encouraging participants to think about Leiden’s environment and history in a playful way. However, some reviews mention that certain puzzles need clearer explanations, especially regarding answers involving weights or pigeons.
One notable review reports encountering app crashes that hindered progress, especially after completing the first station. The tour provider acknowledges this issue and offers assistance via email. It’s advisable to download the app in advance and ensure a stable internet connection.
Plus, some puzzles have been flagged as needing work, with suggestions that adding explanations after questions could improve the experience. The provider has indicated they are working on addressing these issues.
This tour is part of a selection of activities available in Leiden, including options like Spring cruise through Lisse, fast-track Keukenhof tickets, and escape tours. While each offers a different way to experience Leiden and surroundings, this self-guided puzzle tour uniquely combines interactive learning with sightseeing, appealing especially to those who prefer independent exploration.
This self-guided walking experience suits families, small groups, or solo travelers who enjoy a mix of sightseeing and puzzles. It’s ideal for visitors with a curiosity for history and interactive activities. Those expecting a perfectly polished app might find some puzzles need refinement, but overall, it remains a charming way to see Leiden at your own pace.
The “Stolen Keys” tour offers a cost-effective and flexible way to discover Leiden’s highlights. Its main strengths are the engaging puzzles, iconic landmarks, and the ease of self-guided exploration. However, potential technical issues and puzzle clarity should be considered when planning your visit.
For travelers seeking a light, interactive activity that combines sightseeing with a bit of brainwork, this tour can be a fun addition to your Leiden itinerary. Just remember to download the app beforehand and be prepared for some minor hiccups along the way.
“The route was nice and indeed took 1 to 2 hours. Some answers/puzzles were either wrong or needed more info (like with the weights or pigeons).”
Is this tour suitable for children?
Yes, the puzzles are designed to be fun and engaging, making it suitable for families.
Do I need to bring anything besides my smartphone?
You should have your smartphone, internet connection, and data, as these are not included.
Can I start the tour at any time?
Absolutely, the tour has no fixed starting times and can be initiated whenever you’re ready within opening hours.
Is there a refund if I cancel?
Yes, full refunds are available if you cancel more than 24 hours in advance.
Are there any accessibility considerations?
Most travelers can participate, and service animals are allowed, but the route involves walking through city streets and may not be suitable for those with mobility issues.
What if the app crashes or I have technical issues?
You can contact the provider via email at [email protected] for support, and they have acknowledged some puzzles need refinement.