Denmark can look back on a long tradition and eventful history and forms the link between Scandinavia and the rest of mainland Europe. The country is famous for its thousands of islands and rugged coastlines, and Greenland is Europe's only direct border with Canada. But Denmark also has many beautiful lakes, which, with their natural beauty and rich flora and fauna, have a very special charm.
How would you like to hike around Denmark's ten largest lakes and win the coveted collector's medal from the Iron Lake Challenge in the “Denmark” edition?

RULES
The rules for Iron Lake Challenge Denmark are very simple. Nevertheless, we would like to clarify them once again here:
- Sign up for Iron Lake Challenge Denmark!
- To complete the Iron Lake Challenge Denmark and earn the beautiful collector's medal, you must hike around the ten largest lakes in Denmark after registering. Lakes that are partially located in other countries do not count towards this challenge.
- Bicycles, roller skates, etc. are not permitted, but you are welcome to walk or run.
- Each lake must be circumnavigated “in one piece,” unless special rules apply (see below in the descriptions of the lakes). This means that you are allowed to take breaks, but you should complete the lake within one day. Of course, you are welcome to spread the 10 lakes over different days. Only take one lake per day, because you want to enjoy this time too!
- Iron Lake Challenge Denmark has no time limit. This means that you can cycle around the ten lakes over several years.
- We trust that you have indeed run around the lakes. However, if you wish to be included in the time registration, we need a copy of your tracking data. It does not matter what you use (watch, smartphone, or app).
Important general information!
- Please note that traffic rules apply in public spaces and along roads and cycle paths. Therefore, please move carefully.
- You bypass the lakes at your own risk and responsibility. The operator of this website accepts no responsibility.
- Follow any medical advice or consult a doctor before starting the challenge. You are responsible for your own health, equipment, and fitness. There is no shame in stopping a trip—your health always comes first!
A few important rules for interacting with nature during your tour around the lake:
- Be aware of local regulations regarding nature conservation.
- Please do not walk outside the paths.
- Please underline.
- Please refrain from collecting rocks or minerals.
- Please do not pick mushrooms.
- Don't leave trash behind. On the contrary. Many of us even pick up trash.
- Please do not feed the animals.
- Please refrain from lighting open fires.
- Please do not pick plants.
It should really be obvious to all of us, but it doesn't hurt to remind ourselves of it from time to time.
REGISTRATION AND SERVICES
Registration for Iron Lake Challenge Denmark costs €24.
This entry fee includes our Iron Lake Challenge “Denmark Edition” collector's medal and the bullet from Timeless Challenge.
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But first, you have to sail around the ten largest lakes in Denmark! Only then will we send you your well-deserved medal and ball! After all, you want to earn them, not just have them handed to you.
Here's how to sign up:
- Click on the logo to be redirected to the registration page of our partner Digistore24.
- You will now receive confirmation of your registration.
- Now you must walk around the ten largest lakes in Denmark (see below). Once you have completed the ten lakes, send us an excerpt from your tracking as proof. We believe you, even without tracking, but you will not be included in the honor roll.
- Once we've checked it, you'll get your well-deserved medal and bullet. Easy, right?
YOUR MEDAL AND YOUR MARBLE
Once you have hiked around the ten largest lakes in Denmark, you will have earned the beautiful Iron Lake Challenge “Denmark Edition” medal. It could be the first in your future Iron Lake Challenge collection.
In addition, you will receive (from our Timeless Challenge series) the Marble from Timeless Challenge.
LIFE SCORE POINT
The Iron Lake Challenge is part of our Timeless Challenge. Therefore, in addition to the collector's medal and coin, you will also earn Life Score points. These will be automatically credited to our honor roll. This achievement is free of charge for you.
The ten largest lakes in Denmark
Denmark's lakes are truly diverse and beautiful. Unfortunately, we were unable to include the brackish water lake Saltbæk Vig, as the only way to get around the lake is via the dike, and it is not permitted to walk on the dike due to nature conservation regulations. Tømmerby Fjord should also be on the list of Denmark's ten largest lakes, but you can only get around the lake via a busy road, so we have chosen to leave it out.
Arresø
Arresø was originally a fjord arm from the Kattegat and was formed approximately 2,000 to 3,000 years ago when the land north of the lake slowly rose, separating the lake from the sea. Today, the lake is an important bird sanctuary and also popular among people seeking recreation in the local area. The circumference of the lake is approximately 41 kilometers (depending on the route chosen).

Suggested route for a trip around Arresø
Esromsøen
Esrom Lake is located on the island of Zealand. Scientists believe that the lake was formed by a giant ice block from the Ice Age, which has now melted. Today, the lake is very popular for all kinds of water sports, but hikers and runners can also enjoy themselves on the lake's shores. It takes about 28 kilometers to walk around the lake.

Suggested route for a trip around Lake Esrom
Mossø
Mossø is located in the southern part of Søhøjlandet and is characterized by wonderful nature. During your hike, you should definitely climb “Zuckerhut,” a steep hill (108 meters) at Klostermølle, because from here you have one of Denmark's most beautiful views with a fantastic view of Søhøjlandet and Mossø. The trip is approximately 28 kilometers long.

Suggested route for a round trip around Mossø
Stadil Fjord
The freshwater lake is shallow, with a maximum depth of only 2.5 meters. Stadil Fjord, together with Vest Stadil Fjord, has been designated a protected wetland area. A hike around the lake is approximately 30 kilometers long and very beautiful.

Suggested route for a round trip around Stadil Fjord
Tissø
Lake Tissø is located only about 4 km from Höng. The nature reserve has a rich bird life, but is especially known for its archaeological finds from the Viking Age. After your approximately 20 km long trip around the lake, you should definitely visit the permanent exhibition.

Suggested route for a trip around Lake Tissø:
Furesø
Furesø is Denmark's deepest lake with an average depth of 13.5 meters and is protected as a “Natura 2000 area.” Thanks to its proximity to Copenhagen, the lake is easily accessible by car or bicycle. And it is definitely worth a visit, as it offers fantastic nature, water sports opportunities, and good dining options. A trip around Furesø is approximately 21 km long.

Suggested route for a trip around Lake Furesø
Skanderborg sø
Skanderborg Lake is located in the immediate vicinity of Skanderborg, approximately 2 kilometers from the lake. The lake is well-known and popular among anglers, as it offers a wide variety of fish species. However, water sports enthusiasts and hikers will also find something to enjoy. The lake is approximately 20 kilometers long.

Suggested route for a trip around Skanderborg Lake
Søndersø
Lake Søndersø is located in the Maribo Lakes Nature Park and is the largest of the lakes. The landscape, characterized by estates and surrounded by fields, meadows, marshes, and forests, invites exploration. With its 852 hectares, Søndersø is the largest of the lakes. It consists of three basins and is Denmark's lake with the most islands. A trip around the lake is approximately 23 kilometers long.

Suggested route for a trip around Søndersø
Tystrup Sø
Tystrup Lake is located near Fuglebjerg (Zealand). The lake rarely freezes over in winter, as it is very deep and has many springs. A walk around Tystrup Lake is approximately 21 kilometers long.

Suggested route for a trip around Lake Tystrup:
Julsø
Julsø is part of the Silkeborg Lakes, a huge water system in central Denmark. With a water area of 565 hectares, there is plenty of space for water sports. But the shores are also beautiful and invite you to take a walk around the lake.

Suggested route for a hike around Julsø
Iron Lake Challenge Denmark HONORARY PLACE
Here you can quickly and easily register your laps and upload proof (e.g., a screenshot of your tracking). We will check them and then approve them. Your result will then be saved and displayed on the honor roll.
How our honor roll works
- Register on our website.
- Select the lake you have circumnavigated under “Summit/Lake.”
- Enter the distance you have covered (in meters) under “Length / Mountain height (in m)”.
- Enter the time needed (in minutes) under “Time needed (in min)”.
- Enter the date of your visit under “date.”
- Now you can upload the proof (e.g., a screenshot of your tracking) under “Upload proof (optional)”.
- Now just SAVE!
- We will check your round and approve it. You will then be able to see your result in the rankings.
Points
THE IRON LAKE CHALLENGE ON SOCIAL MEDIA
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Share your experiences in our community! Our forum for experiences, reports, questions, and much more.

HASHTAGS OF THE IRON LAKE CHALLENGE
We would love for you to share your photos, videos, and experiences from the Iron Lake Challenge with others. To that end, we have provided the following hashtags:
- #ironlakechallenge
- #ironlakechallengedanmark
- #timelesschallenge
IRON LAKE CHALLENGE ON FACEBOOK
We also warmly invite you to join our Facebook group, “Iron Lake Challenge Discussion Board.”



