History you can touch and feel

Enjoying the views in cozy comfort

The largest castle ruin in Northern Europe

On a steep rocky promontory at the northern tip of Bornholm sits the impressive medieval fortress of Hammershus. It is a perfect destination for the whole family, offering an exciting mix of adventure and history, nature and relaxation in the comfortable visitor’s center powered by green, geothermal energy.

Hammershus is Scandinavia’s largest medieval fortification. It is situated 74 meters above sea level on Hammeren at the northern tip of the Danish island of Bornholm in the Baltic Sea.

Visitor center benefits from Thermia heat pumps

The site consists of the main castle residence and the imposing Mantel Tower, and is surrounded by a great wall of stone that stretches 750 meters around the castle grounds.

Originally constructed in the early 13th century, it was long believed that the castle was built as a private residence for the Archbishop of Lund. However, recent evidence uncovered at the site suggests that it was constructed as a royal residence for Valdemar II of Denmark and as a base for the Danish crusades. The Hammershus fortress was fought over by various Danish and Swedish kings and changed hands several times throughout its storied history. For the first 500 years of its life, Hammershus served as the stronghold of the island’s various rulers. The fortress was rebuilt and extended on several occasions. In 1822, the ruins were placed on the national historic register.

Thanks to this modern and efficient geothermal energy system, visitors, guests, students and employees can learn about Danish history in comfort. At the same time, the Danish Nature Agency is able to save money while Bornholmers make a direct contribution to become carbon neutral.“

The Hammershus visitor center extends to around 850 m2 and features an exhibition space, souvenir shop and restaurant. It is open all year round. The heating and cooling system is based on Thermia Mega XL (21-88 kW), a new commercial ground-source heat pump with an inverter-driven compressor.

The main advantage of this heat pump is that it can continuously adjust heating or cooling output to current demand. In addition, the Thermia Mega can also provide simultaneous heating and cooling. If the primary function is cooling, any heat surplus is used to produce hot water. The new energy solution has enabled the Danish Nature Agency Ministry provide extremely energyefficient heating and cooling that is sustainable and renewable while guaranteeing superior comfort. The Hammershus visitor center is an excellent example of modern architecture that perfectly blends into its historical landscape setting and uses a high level of sustainable and green technology.


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