The Megalithic Giant Stone (Riesenstein) of Heidelberg

View of the megalith with incorporated stairs. It is not visible at this angle, how this rests on the other stone block. You can easily see the foundation, which appears like a stage. On the left the smoothed quarry wall and on the lower right another huge block. Unfortunately, it is no longer possible to see where this one once was, resp. whether it has always been there.

The Riesenstein rests on the slopes of the Gaisberg mountain, overlooking Heidelberg’s historic town and within view of the renowned Heidelberg Castle.

On the other side, spanning a few hundred meters across the Neckar River, lies the Heiligenberg (Mountain of Saints). This enchanting place holds a rich history of settlement and religious devotion, spanning over 7000 years.

Find a video of the location at the bottom of the page.

Throughout history, the hill has been shaped by various civilizations, including the Celts, Romans, Christian monks, and more recently, the Nazis. These influences have left lasting imprints that can still be seen today. Remnants of ancient circular ramparts, temple ruins, and monasteries serve as reminders of the past. Notably, a grand Nazi cult complex, reminiscent of an ancient amphitheater, stands as a testament to the intertwining of history and architecture on this hill.


Riesenstein is actually the name of the old quarry area from which parts of Heidelberg Castle and other historic buildings in the town were constructed over the past centuries. The most captivating aspect is the presence of two immense megalithic stone boulders, arranged in a vertical stack before the backdrop of a once-active quarry wall.

It is not entirely implausible to speculate that the boulders may have had some connection to the ancient and contemporary sites situated on the Heiligenberg nearby.

These massive blocks, each weighing tens of tons, rest upon a platform seemingly crafted for that purpose on this slope. The enigma lies in their origin and the hands responsible for their placement.

According to the official account, they purportedly collided from above, presumably during the 17th century, and settled into their current positions.

Two megalithic blocks are half stacked on top of each other

One cannot help but be immediately drawn to the intricately carved staircase in one of the two rocks.

It is hypothesized that the workers began crafting a workpiece right at the quarry site, with the intention of delivering the finished piece intact at a later time. To achieve this, they commenced working on that fallen boulder. However, they inexplicably left their work unfinished. Assessing the plausibility of this scenario will lead you to your own conclusion.

Stairs carved into ancient megaliths and pagan sacrificial stones are a recurring occurrence in various places around the world.

Some of the photos reveal that the stones are positioned on a platform resembling a stage, as if it was meticulously crafted for that very purpose. Additionally, beyond the boulders, there is a quarry wall that seems to have undergone a similar process of refinement and smoothing. A typical conventional quarrying operation often results in walls that are rough and uneven, with deep holes caused by the broken-out blocks.

Stairs have been carved out of one of the two megaliths

Support stones can be found in different locations between the contact surfaces of the two megaliths and the underlying platform. One of these stones is a larger block, while the others resemble brick masonry.

The larger stone is securely in place, seemingly not serving a load-bearing purpose upon closer examination, though. The megalith that has entrapped him rests safely atop the other one. Whether and for what purpose it was subsequently pressed in cannot be determined beyond doubt.

The same predicament applies to the masonry. It remains firmly fixed, yet whether it bears the weight of the colossal megalith above it remains uncertain. If the latter were indeed proven, and it would have been placed there before the megalith was stacked on top, we would be confronted with an unequivocal sensation in the history of south and southwestern Germany. There has never been any official record of a megalithic culture in that region.

Support stones between the megaliths and their underlying platform

Below are some more impressions from the immediate vicinity of the Riesenstein where you can find other massive carved stones lying around.

The site appears to be situated along an ancient border, reminiscent of a time when Germany was still a patchwork of distinct kingdoms, duchies and the like. Often these supposed old quarries as well as other ancient places of worship can be found on or close to such borders.

Furthermore, the medieval nobility often had a penchant for constructing their castles in proximity to such sites, much like the Catholic Church’s inclination to establish its monasteries there. Both are exemplified here by the majestic Heidelberg Castle and the remnants of two monasteries, now in ruins on the adjacent Heiligenberg. These guys likely desired to harness the energies of these locations for their own purposes.

Impressions from the Riesenstein vicinity

This video showcases the Riesenstein area, featuring the two megaliths stacked on top of each other.

Video: Riesenstein

Below is a map of the old town of Heidelberg, showcasing key landmarks such as the Gaisberg, home to the Riesenstein, and the Heiligenberg (Mountain of Saints), situated across the River Neckar. Additionally, the Heidelberg Castle is located not far to the northeast.

Map of Heidelberg and the Riesenstein location

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