On the eastern corner of the Danish island of Funen, the romantic birthplace of Hans Christian Andersen, Knud Erik Hansen found love at first sight.

The object of desire for the chief executive officer and third-generation owner of furniture makers Carl Hansen & Son and Rud. Rasmussen was Hellerup Manor, a castle dating back to 1670, complete with its own moat.

After buying the listed property in 2002, Hansen and his wife, Dr. Inger Marie Jensen Hansen, spent more than a decade painstakingly updating it with modern conveniences.

"The kitchen was completely out of date," Hansen explains. "And there was only one bathroom for a home with nine bedrooms." He adds that the new kitchen, in its original basement location, respects the past while incorporating the latest in design.

"At one end you have the wood-burning fireplace, where they used to cook in the 17th century, and on the other a brand-new Bulthaup kitchen, all in oak." The addition of five more bathrooms was a must for a house that sees a constant stream of visitors, including the couple's two grown children.

Given the strict rules surrounding such historic landmarks, no changes could be made to the external appearance of the 23,000-square-foot home, only refurbishments. Conservation architects Bue Beck and later Thomas Hillerup from Design Studio Vaag designed seamless updates to the structure, and teams of artisans skilled in old-world craftsmanship worked to restore details-with Denmark's Agency for Culture and Palaces approving every change.

But the true magic lies in how Hansen reimagined the interior spaces and filled them with furniture the company produced during his tenure and his father's. (The brand will open a flagship store in New York in February, their second standalone stateside location.)

These contemporary pieces, designed by the likes of Hans J. Wegner, Morten Gottler, and Tadao Ando, complement the structure's dramatic lines and instill it with a sense of hygge, the Danish concept of cozy living.

"You wouldn't expect to see furniture produced from this century in this setting," Hansen says. "But when people come to see us, they say it looks like the house was designed for the furniture."

Layers of paint on the historic walls were scraped back to discover the original colours: a deep, dark red in the south-facing living room, and lighter colours toward the northern side, which gets less light. Some floors are painted in a light gray oil paint to brighten the rooms, but most have the original old, broad Douglas fir pine-floor planks.

Most recently, Hansen renovated the attic. The additional 5,000 square feet of living space highlights the original exposed Pomeranian pinewood beams and creates a library space with sloping skylights.

While he contemplates the next area of renovation, Hansen is focused on the upkeep of his almost 7 acres of land, which he enjoys mowing himself on "the biggest John Deere you can buy."