Denmark's biggest lake isn't natural at all. Tange Sø, a long crooked stretch of water in the middle of the Jutland Peninsula, was created in 1920 when the River Gudenå was dammed to generate hydroelectric power. A century later, the hydro plant is still there — and the lake has quietly become one of the country's best spots for fishing, hiking and slow, outdoorsy breaks.

Getting there takes a bit of effort, which is part of the appeal. There's no big city nearby — Vejle, Denmark's tenth-largest city, is nearly 100 kilometres away by car. The practical route in is Billund Airport, well connected to Copenhagen and international destinations, from where you can base yourself in the lakeside towns of Viborg or Silkeborg and explore the surrounding Jutland countryside.

Fishing is the headline act. The flooded stretch of the Gudenå between Ans and Bjerringbro holds perch, pike, zander, roach, brown trout and eel, and fishing here is a year-round affair. The rules matter, though: Tange Sø is not a catch-and-release-without-a-licence lake. You'll need a Danskfiskekort (Danish fishing licence), bought online from the Danish Agricultural and Fisheries Agency, and sometimes an additional agency licence. Size limits and closed-season zones apply for conservation. Tourists can fish but can't sell their catch, and shipping fish back to the US involves special permits — so the simplest plan is to rent a holiday home or campsite and cook your dinner fresh. Children under 12 fish free, and 13-to-16-year-olds are covered when accompanied by a licensed adult. Tip from anglers: target headlands and reed-heavy stretches for pike.

Not into fishing? There's plenty more. Swimmers get easy access via wooden piers at Tange Sø Marina in Ans. From May to September, a solar-powered boat runs a 45-minute trip from the bridge at Fiskeriet to the bridge at Frisholtvej, passing the Energimuseet — an interactive electricity museum housed beside the historic Tange power plant. You can ride back or walk the return leg on a peaceful trail through woods and pasture, with small towns and picnic spots along the way.

Tange Sø suits travellers who like their holidays low-key and green: anglers, hikers, families with rods and bikes, and anyone who's done Copenhagen's museums and wants to see the Denmark Danes actually escape to. Combine it with Billund's Legoland, Silkeborg's lakes region or a detour to Bornholm for a proper under-the-radar Danish trip.