Underground water tanks of Brno
Discover Brno's hidden underground water tanks on Žlutý kopec, where cool, historic spaces blend with art and offer a unique refuge from the summer heat.
Nestled beneath the surface of Žlutý kopec, or Yellow Hill, in Brno lies a hidden gem—a series of underground water tanks that have been part of the city’s history since the late 19th century. These massive structures once held the lifeblood of Brno’s industrial era. Today, they stand as a testament to both the ingenuity of past generations and the city’s ability to transform forgotten spaces into places of wonder and reflection.
As you step into the second of these water tanks, built in 1894, you are immediately struck by its almost cathedral-like atmosphere. The space is defined by dozens and dozens of brick columns that rise up to support a beautifully crafted brick archway, giving the tank an ethereal quality. The concrete floor below, often dotted with small puddles, reflects the structure above, creating an otherworldly ambiance that is both calming and awe-inspiring.
This tank, along with its counterparts, was once filled to the brim with water, serving the city of Brno from 1874 until 1997. “The water here was non-potable, meaning it was primarily used for industrial purposes,” explains Hana Bánovská from the Brno Tourist and Information Center. After nearly 120 years of service, the tanks were forgotten, sealed off from the public, and left to the darkness. It wasn’t until 2000s that a group of local adventurers, who were exploring Brno’s underground, rediscovered these hidden spaces. They saw the potential in these forgotten tanks and worked tirelessly to have them recognized as protected technical sites. Their efforts paid off, and by 2020, the first tank was reconstructed and reopened to the public.
The restoration and opening of these tanks have turned them into a unique attraction that offers visitors an escape from the heat during Brno’s scorching summers. “It’s truly perfect,” says Bánovská. “Throughout the year, the temperature inside the tanks remains a cool 14 degrees Celsius. Whether it’s hot, rainy, or cold outside, this place offers a consistent and comfortable refuge.”
The cool, moderate climate of the tanks makes them an ideal spot not just for relaxation, but also for cultural experiences. Recognizing the special atmosphere of these underground spaces, the city has initiated a project called Vodojemy Art. This initiative aims to bring art into the tanks, hosting a variety of performances and exhibitions. “We’re open to a wide range of artists and art forms,” Bánovská shares, “from musicians to florists, painters, and beyond. The unique setting of these tanks enhances the experience of any artistic presentation.”
Located on Žlutý kopec, just a short stroll from Brno’s city center, the tanks are situated in a residential area near a hospital. While parking can be challenging, the tanks are easily accessible on foot, making them a convenient destination for both locals and tourists. The location itself also tells a story of technological evolution. “The first tank, built in 1874, was made with handmade bricks produced in Brno,” Bánovská explains. “These bricks needed to be heated to 1,000 degrees Celsius to ensure they were compact and waterproof. By the time the second tank was built 20 years later, bricks were mass-produced, reflecting the advancements in industrial technology. The third and final tank, constructed in 1917, was made entirely of concrete, showcasing the rapid development in building materials over just a few decades.”
One might wonder how water was brought to these tanks, perched as they are on a hill. The solution was simple but effective—water was pumped from the nearby Svratka River, the main water source for Brno. However, the quality of the river water wasn’t ideal, prompting the construction of the third tank, which was supplied with cleaner water from Březová nad Svitavou, a village north of Brno.
The Žlutý kopec water tanks are just one of many underground attractions in Brno. The city is renowned for its subterranean sites, offering visitors a chance to explore its ossuary, the labyrinth under the vegetable market, and the cellar beneath the new town hall, where animated stories bring Brno’s history and myths to life. For those looking to cool down during the summer, these underground spaces offer a refreshing alternative to more traditional outdoor activities.
For those interested in visiting the water tanks, Bánovská suggests downloading audio guides from the website watertanks.no.cz before heading underground, as there’s no Wi-Fi available. “These audio guides, available in English, German, and Polish, provide a deeper understanding of the tanks’ history and significance,” she says. Without the distractions of modern technology, visitors can fully immerse themselves in the cool, tranquil environment, enjoying a form of relaxation—or even meditation—that’s difficult to find elsewhere.
As the visit comes to an end, Bánovská offers a final piece of advice: “If you’re here on a hot day, it’s really a relief to come to a place like this. Just be careful when you go back up—it’s really hot outside, so take care, as it can be a bit of a shock.” Her words encapsulate the unique allure of the Žlutý kopec water tanks—a place where history, architecture, and nature converge to offer a cool, peaceful retreat from the world above.
