Deep beneath the forests of Lower Silesia lies one of World War II's most enigmatic construction projects - the massive underground complex known as Project Riese. These sprawling tunnels and bunkers, built by the Nazis using forced labor, continue to captivate explorers and historians with their mysterious purpose and legends of hidden treasure. Today, visitors can venture into these haunting subterranean passages where Josh Gates searched for the famous lost gold train.
The Lower Silesia Underground Complex, known as Project Riese (German for "Giant"), is a network of underground tunnels, bunkers, and unfinished facilities carved into the Owl Mountains of southwestern Poland. The complex consists of seven main construction sites spread across approximately 35 square kilometers, with tunnels extending hundreds of meters into the mountainside. During World War II, the Nazi regime employed thousands of forced laborers to excavate these massive chambers, though the project's ultimate purpose remains debated among historians. Gates investigated the site while exploring legends of a buried Nazi gold train reportedly hidden in the region's extensive tunnel network.
Nazi Germany begins Project Riese construction using forced labor from concentration camps
Project abandoned incomplete as Soviet forces advance; tunnels sealed and partially destroyed
Polish authorities announce discovery of possible buried train via ground-penetrating radar, spurring renewed international interest
Gates investigates the underground complex and gold train legend for Expedition Unknown
Historians studying Project Riese generally agree that the complex was part of a larger Nazi strategy to move strategic operations underground as Allied bombing intensified, though the specific intended use of each tunnel system remains uncertain. The project employed forced laborers from nearby concentration camps under brutal conditions, and thousands died during construction. Mainstream historical research focuses on documenting the complex as a testament to both Nazi engineering ambitions and the human cost of forced labor programs.
The legend of the Nazi gold train gained international attention in 2015 when treasure hunters claimed ground-penetrating radar revealed a buried train in the region. Polish authorities took the claims seriously enough to authorize limited excavation, though subsequent investigations by professional archaeologists and geologists found no evidence of a buried train. Most experts now consider the radar anomalies to be natural geological formations or war-era tunnel collapses rather than hidden treasures.
Gates' investigation of the site contributed to documenting the physical reality of the underground complex for a general audience, exploring both the verified history of forced labor construction and the more speculative treasure legends. The episode balanced examination of genuine historical atrocities with investigation of popular treasure stories, demonstrating how World War II sites in Eastern Europe continue to generate both serious scholarship and sensational claims. While the gold train legend remains unproven, the episode highlighted how Project Riese itself represents a significant and somber historical site regardless of whether hidden treasures exist.
Today, several of the Project Riese tunnel complexes are open to visitors as historical sites and museums, allowing the public to witness the scale of Nazi underground construction efforts while memorializing those who suffered and died building them. The sites serve educational purposes, with guided tours explaining both the construction methods and the broader historical context of forced labor in Nazi Germany.
Project Riese involved excavation of an estimated 200,000 cubic meters of rock, creating one of the largest underground construction projects undertaken by Nazi Germany.
The complex's seven main sites each have codenames: Osówka, Włodarz, Rzeczka, Soboń, Sokolec, and two sections known as Jugowice.
Despite massive investment of labor and resources, none of the Project Riese facilities were ever completed or put into operational use before the war ended.
The tunnels were briefly used by Polish military after World War II before being sealed, and some sections weren't reopened until the 1990s and 2000s.
Several sections of the Project Riese complex are open to tourists, with the Osówka and Rzeczka tunnel systems offering the most developed visitor facilities including guided tours. The sites are generally accessible year-round, though visitors should expect cool temperatures underground and wear appropriate footwear for uneven surfaces. Some tunnel sections require advance booking and may have restrictions on photography or group sizes.
Wałbrzych, Poland, approximately 8-15 kilometers from various Project Riese sites.
Spring through early fall (May-September) offers the most comfortable weather for traveling to the mountain sites, though the underground tunnels maintain constant cool temperatures year-round. Summer months can be crowded with tour groups, while shoulder seasons may offer a more contemplative experience.
Underground tunnel system (Nazi art storage)
Another underground tunnel complex used by Nazi forces to hide valuable items, representing similar efforts to conceal assets and operations as the war turned against Germany.
Toplitzsee Lake
Austrian alpine lake investigated for Nazi treasures and rumored gold deposits, part of the broader search for hidden Nazi valuables across Central Europe.
Best time to visit: Visit during spring through early fall (April-October) when weather conditions are most favorable for underground exploration and surface access roads are clear.
Travel tip: Bring warm clothing and sturdy walking shoes as the underground tunnels maintain cool temperatures year-round and surfaces can be uneven and damp.