Auto-Pédestre Mertzig – Turelbaach Castle

9km – Easy / medium – 3 hours
The best way to hike to the whimsical, mysterious Château de Turelbaach
Park and start at 12, rue de Merscheid, L-9169 Mertzig
By bus: Mertzig Gemeng

There’s really only one reason to hike the Auto-Pédestre Mertzig – but it’s a compelling one! The moss-cloaked, turreted oddity that is the Château de Turelbaach (or “Turelbach”) is one of Luxembourg’s most photogenic castles. But… is it really a castle at all? We laced up our boots in the spacious car park of Mertzig’s Gemeng and set off to find out.

This is the newest of the 150+ “Auto-Pédestre” trails in Luxembourg (opened in 2023). These trails have been staples of the Luxembourg hiking scene for decades, originally intended to highlight circular loops easily accessible by car (hence the name). As part of a recent revamp, over 50 “APs” have been decommissioned, many because they included sections along roads open to traffic, which became dangerous as traffic volume increased around the country.

It was a little surprising, therefore, to find that the first kilometre or so of the AP Mertzig reverted back to these dark days: a longish section on a narrowish road with the occasional vehicle zooming past. After a while the little blue diamond veered to the right and we were, finally, in the serene woodland of central Luxembourg.

After a few quiet kilometres, the trees opened suddenly onto a sheet of glass. The lake mirrored every branch and cloud so precisely it felt unreal. The air was sharp and clean, the forest floor damp and fragrant, and sunlight poured into the clearing with a strange, late-season glare.

This is the lake on which Turelbaach was built… and it’s man-made. In the not so distant past (the 1960s) this was marshy woodland and meadow, fed by the gushing Turelbach stream. Then one man had a dream… and everything changed.

Let’s face it: we all dream of living in a fairy-tale castle. But for Pol Gilson – a native of Mertzig – dreaming wasn’t enough. He wanted to build a fairy-tale castle. He cleared the woodland, dredged the marshy meadow, used the excavated soil to build two artificial islands in his newly-created lake and started work on his fantastical château. His first effort – a wooden construction – burnt down in 1973, but this unfortunate setback only increased his resolve. Undeterred, he rebuilt, but this time in stone and concrete, using recycled materials where he could (including, allegedly, real tombstones…), and working mostly by hand right up until his death in 2007 – a true lifelong passion!

Turelbaach was never open to the public; Pol and his family used it for recreation, music and nature. Since no public footpaths led to the castle it remained hidden, an almost-mythical place in Luxembourg. In 2020 the commune of Mertzig stepped in, acquiring the property, and since 2022 it enjoys protection as a national cultural heritage site. Today, a hike around the Auto-Pédestre Mertzig gives an almost-360° tour of the exterior and grounds, though the interior remains private, and development into a public cultural and nature site is ongoing.

Leaving the castle and lake behind, the path heads back towards Mertzig again, briefly flirting with patches of pretty woodland before giving up on trying to be attractive and making a beeline for the village through open farmland. There’s a small twist at the end of the trail, a brief tour of the park, old houses and riverside walk in Mertzig itself, a nice nod linking this humble town to its star attraction.

A final thought: we were totally alone at Turelbaach Castle today, a perfectly sunny school holiday. It’s clear to see the potential that this unique place has for tourism, and I can’t help but wonder how Luxembourg will “market” this place going forward. I wouldn’t be surprised at all to see Turelbaach developed and promoted into a major tourist attraction, so catch it now before the whole world does!

Whatever its future, Turelbaach remains one of Luxembourg’s strangest and most captivating creations. Part dream, part devotion… and an unforgettable reason to lace up your boots and get out into the woods.