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Explore Trier's underground Roman sites with this 2-hour small group tour, including excavations beneath the Constantine Basilica and imperial baths.
Experience Trier’s Roman past from a secret underground perspective with the “On Imperial Trails – Underworld tour” offered by Trier Tourismus und Marketing GmbH. This 2-hour small group adventure takes visitors beneath the city streets to explore sites normally inaccessible to the public, making it perfect for history buffs and Roman enthusiasts. With a provider rating of 4.6, this tour promises engaging storytelling and exclusive access to Trier’s hidden Roman underworld.
The tour starts at the Constantine Basilica, with guided visits to excavations below the basilica, as well as the cryptoprocticus, a mysterious underground walkway. End the experience inside the Imperial Baths, where supply tunnels and water channels reveal the grandeur of ancient bathing culture. The tour is designed for adults over 15 years, as it involves underground exploration and walking through confined spaces.
While the tour offers unique access and in-depth insights into Trier’s Roman history, it’s important to note that wheelchair users and children under 15 are not suitable** for this experience. The small group size ensures a personalized feel, and the live German guide adds an authentic storytelling touch. Advance booking with free cancellation up to 24 hours before helps travelers plan flexibly.


The tour begins in front of the Constantine Basilica, a grand Roman structure. From here, the guide leads you into excavations located directly beneath the basilica, revealing the foundations of the Roman audience hall. You’ll get a tangible sense of how the ancient Roman elite once gathered in these impressive spaces.
The visit to the underground remains is a rare opportunity to see Roman construction techniques and architectural details that are normally hidden. The excavation site not only showcases the grandeur of the past but also offers insider insights into Trier’s Roman history, making it a highlight for history lovers and those curious about ancient architecture.
The tour’s short duration means you’ll see a lot in a concentrated time, with the guide providing fascinating stories about the significance of these structures and their role in Roman Trier.
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One of the most exciting parts of the tour is visiting the locked cryptoproporticus. This underground corridor is part of a luxurious Roman city villa and remains locked and inaccessible to the general public.
The guide explains the mysterious nature of this underground walkway, highlighting its luxury and complexity. You’ll hear stories about the villa’s owners and the function of these underground passages, which add a layer of intrigue to the Roman city’s sophisticated infrastructure.
This hidden walkway exemplifies the exclusive Roman lifestyle and wealth, providing a glimpse into private Roman luxury that few get to see firsthand. The cryptoproporticus underscores the tour’s focus on unveiling secret parts of Trier’s Roman past.

The Imperial Baths offer another highlight of the tour: walking through the ancient supply corridors. This area once facilitated water flow and bathing rituals for Roman citizens.
The guide explains how water was delivered and the role of workers in maintaining the baths. Visitors can see channels, tunnels, and water systems that demonstrate Roman engineering prowess. It’s a compelling way to understand public bathing culture in ancient Rome and see the scale of Roman infrastructure up close.
The underground passages are narrow and atmospheric, making it a memorable part of the journey. This stop reveals practical aspects of Roman life that are often overlooked in traditional sightseeing.

The tour departs from the front entrance of the Constantine Basilica, located at coordinates 49.75338363647461, 6.64335823059082. The meeting point is straightforward and convenient, right in front of this iconic Roman monument.
The small group format ensures an intimate experience, with the guide leading the way through confined underground spaces. The duration of 2 hours allows for a thorough exploration without fatigue, but participants should be prepared for some walking and standing in enclosed, underground conditions.
This tour is not suitable for wheelchair users, due to the nature of underground passages, and children under 15 years are also discouraged from joining.
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The live guide speaks German, delivering approachable yet informative narration. The guides are experienced in Roman archaeology and local history, providing stories that engage and enrich the underground exploration.
This focus on authentic storytelling helps bring Trier’s Roman past alive. While some content is shared in the original language, the clarity and enthusiasm of the guide make the experience accessible for visitors with basic knowledge of German.
The tour is bookable with free cancellation up to 24 hours in advance, allowing flexibility for travelers. You can reserve your spot without paying upfront, making it easy to plan ahead.
Starting times vary, so it’s advised to check availability in advance. The provider rating of 4.6 reflects positive feedback on the quality of the experience.
Since the tour involves underground exploration, participants should wear comfortable, sturdy shoes and be prepared for confined spaces.

What makes the “On Imperial Trails – Underworld tour” special is its focus on hidden Roman sites that are not normally open to the public. The exclusive access to underground excavations beneath the basilica and the cryptoproporticus offers a unique perspective on Trier’s Roman heritage.
While it may not suit everyone—particularly those with mobility issues or young children—the small group size and expert guides ensure that you receive personalized attention and authentic stories about Trier’s imperial past.
The combination of above-ground history and underground secrets makes this tour a must-do for fans of ancient Rome looking for a more intimate, behind-the-scenes look at Trier.

Is the tour suitable for children?
No, children under 15 years old are not suitable due to the underground nature of the tour.
Is wheelchair access available?
No, the underground passages are not wheelchair accessible, so this tour is not suitable for wheelchair users.
What language is the tour conducted in?
The live guide speaks German. Some content may be presented in its original language, but the narration is primarily in German.
Can I cancel the tour?
Yes, free cancellation is available up to 24 hours before the scheduled start.
How long is the tour?
The tour lasts approximately 2 hours, covering multiple underground sites.
Where exactly do I meet?
The meeting point is in front of the Constantine Basilica, at the specified coordinates.
Is this a group or private tour?
It is a small group tour, ensuring an intimate experience with personalized guidance.
What should I bring?
Participants should wear comfortable shoes and be prepared for underground walking conditions.
What makes this tour different from others in Trier?
Its focus on exclusive underground excavations and hidden Roman features that are usually off-limits to the public, offering a rare glimpse into Trier’s imperial underworld.
Is the experience rated highly?
Yes, with a provider rating of 4.6, it reflects positive feedback on the quality and knowledge of the guides.
This “On Imperial Trails – Underworld tour” provides a fascinating journey beneath Trier‘s streets, revealing hidden Roman secrets that enrich the city’s storied past. Its exclusive access, small group intimacy, and expert storytelling make it a compelling choice for those eager to see Trier from a rare underground perspective.
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