Walk around Westerlo: castles, an abbey and a river

This walk around Westerlo includes two castles, a Norbertine abbey with a da Vinci secret, a tranquil river, and a nature reserve. All on a single 12 km walk. Updated June 2026.

Westerlo walk at a glance

Where exactly is Westerlo?

Westerlo sits in the province of Antwerp, in the heart of the Kempen. The Kempen is the broad, heathery plateau that stretches across northeast Belgium into the southern Netherlands. Westerlo is called the ‘pearl of the Kempen’, and once you’ve spent a day here, the nickname makes perfect sense. The municipality covers seven villages: Westerlo, Oevel, Tongerlo, Heultje, Voortkapel, Oosterwijk, and Zoerle-Parwijs, with a combined population of around 25,000.

It is not the easiest place to reach by public transport. Westerlo falls into one of those Belgian rail network black holes where the nearest stations (Heist-op-den-Berg and Geel) require a bus connection. By car, though, it is straightforward enough: take the E313 to exit 23. I parked near the Tourist Office on Sint-Lambertusstraat and set off on a pre-planned 12 km circular walk that turned out to be a most enjoyable and varied day out.

The Grote Nete River

The walk begins gently, heading down from the town centre to the banks of the Grote Nete (the Big Nete River). This river is around 85 km long, rising near Hechtel in the province of Limburg before flowing west through Geel, Westerlo and Heist-op-den-Berg. It eventually joins the Kleine Nete at Lier to form the Nete, which feeds into the Rupel and onward to the Scheldt.

What struck me immediately was how well the riverbank had been maintained. Wide, firm footpaths run along both sides of the water, and there are benches at intervals. These invite you to stop, forget your route plan for a moment, and simply listen. Waterfowl on the river, birds in the trees overhead, the occasional heron standing completely still in the shallows. The Grote Nete in this stretch is a genuinely peaceful place. On a clear early morning in late winter, with low light catching the water, it was quite beautiful.

Tip: The riverbank paths connect into the wider De Merode walking node network. If you want a shorter outing, you can follow the Nete alone and return without completing the full loop.

Castle of the Princes de Merode

The first castle appears while you are still following the river, and it announces itself with some confidence. Properly known as Kasteel de Merode (or locally simply as ‘the old castle’) it has been the seat of one of the most powerful noble families in the history of Brabant for more than six centuries.

History

The de Merode family originally came from the village of Merode, between Aachen and Cologne. They obtained the seigneury of Westerlo by marriage in the 15th century and, through a sequence of further advantageous alliances, became one of the dominant forces in the Duchy of Brabant. The castle they built here was no mere country house. It was a statement of power, positioned strategically on the banks of the Grote Nete to control movement across the region.

The site itself is much older than the current structure. The location may have served as a Frankish villa or even a Roman castrum or watchtower. This is because the ground is strategic, sitting at a junction of two ancient roads above a marshy river bend. The rectangular stone keep, or donjon, was built in the 14th century from local brown stone, with walls up to 2.75 metres thick. The present castle in Flemish Renaissance style dates largely from the mid-16th century, though that formidable dungeon with its near-3-metre walls and 10-metre ceiling predates it by at least two hundred years.

The 16th century was a turbulent one for the castle. In 1583, Westerlo served as a stronghold for rebellious nobles from the Spanish Netherlands who opposed Habsburg rule. Later restorations in the 19th century gave the building its current romantic medieval silhouette. Today, the sumptuous interiors (entrance hall, knights’ hall, drawing room, dining room, and chapel) contain centuries of accumulated treasures: furniture, paintings, tapestries, and decorative objects collected by generations of the de Merode family.

Visiting today

The castle remains a private residence, currently the home of Prince Simon de Merode. It is not open on a casual drop-in basis, but it does open its doors on selected occasions. The most important is the Kasteelfeesten (Castle Festival), held on the first weekend of July each year, which gives visitors access to the principal rooms. There are also occasional openings around Christmas. The ‘Friends of Westerlo Castle’, a non-profit organisation established in 2006 under the direction of the Merode family, works to promote and restore the property through sponsorship and events. More info.

Rothoek-Kwarekken nature reserve

The marvellously named Rothoek-Kwarekken nature reserve is next on the route, and it deserves more than the quick walk-through it often gets. This is a roughly 40-hectare mosaic of wetland habitats stretched along the south bank of the Grote Nete, between the Marlybrug (near Kasteel de Merode) and the Snepkensbrug.

Landscape and ecology

The terrain shifts as you move through it: from the higher, drier ground of the Asberg, where oak, beech and pine give the reserve a more conventional woodland feel, down into the low-lying, permanently wet Kwarekken, fed by groundwater from the surrounding higher land. This is a spring-fed area, and the permanently damp conditions have produced a remarkable range of wetland plants. Bogbean, marsh violet, water violet, and several rare sedge and sphagnum species thrive here. The reserve is managed by Natuurpunt (which owns the Rothoek portion) and Kempens Landschap (which acquired the Kwarekken in 2006), with volunteers carrying out regular haymaking, woodland management, and pond restoration.

A birdwatching hide has been built by volunteers almost entirely from reclaimed materials. It overlooks one of the old fish ponds that has been converted into a more open, shallower water body to encourage greater biodiversity. From the hide you can spot waterbirds such as common sandpiper, heron, kingfisher, and reed warbler. Buzzard, sparrowhawk, peregrine, and tawny owl are all recorded here, along with three species of woodpecker: black, green, and great spotted. In summer, damselflies and dragonflies are abundant. In September 2024, the volunteers erected a stork nest, and are now waiting, hopefully, for guests.

Tip: The bird hide is slightly off the main walking network, you will need to deviate from the knooppunten route to find it. Some paths are closed during the breeding season (roughly April–June).

Tongerlo Abbey

Approaching Tongerlo Abbey from a distance across the Kempen fields is one of those quietly memorable moments. The scale of the complex catches you off-guard. It’s a great spread of buildings behind a gateway that speaks of centuries of accumulated importance.

Foundation and growth

The abbey’s origins go back to 1128, when a wealthy landowner called Giselbert of Kasterlee donated his estate at Tongerlo to a small group of monks sent from the Norbertine Abbey of St Michael in Antwerp. The foundation charter was signed by – among others – Bernard of Clairvaux. From that modest beginning, Tongerlo grew into one of the most influential monasteries in the Kempen region. By the 13th century, the Pope had placed the abbey at the centre of a network of parish churches across the area. At its peak, the community was providing priests for around forty parishes. It was a significant centre of learning, with a substantial library and a scriptorium.

Turbulence and survival

The abbey’s history is not a smooth one. The rise of Calvinism in the 16th century brought serious violence: three of Tongerlo’s monks were martyred between 1557 and 1572. Catholic worship was suppressed, and many of the community were driven from their parishes. Then, in 1796, the French Revolutionary forces swept through and the abbey passed into private ownership. The monks were dispersed.

After Belgian independence in 1830, a monastic community was re-established at Tongerlo. But peace did not last: a catastrophic fire in 1929 destroyed much of the abbey complex. The buildings you see today are largely reconstructions from the decades that followed, though several older structures survive, including the 14th-century entrance portal and a late Gothic wing that would later inspire the design of Countess Jeanne’s castle nearby.

Tongerlo also played an unexpected role in the Boerenkrijg of 1798. This was the Flemish peasant uprising against French Revolutionary rule. The Great Barn of the abbey served as a meeting place for rebel leaders plotting resistance. It is a small footnote in a large story, but a vivid one.

The da Vinci connection

Here is the detail that stopped me in my tracks. Since 1545, Tongerlo Abbey has been home to one of the most remarkable works of art in Belgium, and arguably one of the most important copies of a painting anywhere in the world.

When Leonardo da Vinci painted The Last Supper on the refectory wall of Santa Maria delle Grazie in Milan between 1495 and 1498, his students made several full-size copies. The canvas at Tongerlo – covering almost 34 square metres – is believed to have been painted by Andrea Solari, one of Leonardo’s closest assistants, around 1506-07, while the original was still relatively fresh. Some experts believe da Vinci himself worked on certain figures. Art historian Jean-Pierre Isbouts, following IMEC scans carried out at Heverlee, concluded that the face of John shows the unmistakable hand of the master.

The original fresco in Milan has suffered grievously over the centuries. Leonardo experimented with new techniques that proved unstable, and the painting has been damaged by moisture, overpainting, and time. The Tongerlo version, by contrast, has been preserved in its vivid original colours. Many who have seen both say the copy conveys the composition as Leonardo intended it more faithfully than the faded original.

The painting was purchased at auction in Antwerp in 1545 by the abbot of Tongerlo. This was a remarkable act of connoisseurship at a time when the Low Countries were still under the spell of Gothic art. It remained in a dedicated museum building for decades. Following restoration work, the canvas was relocated in 2023 and now hangs in the abbey church itself, facing the main altar.

Practical info: The Last Supper copy can be viewed in the abbey church. Mon-Sat: 8-11 am and 1-5 pm. Sunday: 8-10 am and 1-5 pm. A light switch in the side aisle illuminates the painting for 5 minutes. Free entry. Photography is not permitted near the replica. The abbey grounds are freely accessible. A gift shop sells Tongerlo beer, wines, and memorabilia. 

For more on the abbey’s remarkable tapestry collection housed nearby at the Royal Manufacturers De Wit in Mechelen, see my companion post: Tongerlo Abbey, Mechelen: The Marvel of Flemish Tapestries.

Castle of Countess Jeanne de Merode

The walk saves something special for last. Less than a kilometre from the abbey, on a domain of around 6.5 hectares, stands the castle built by Countess Jeanne de Merode between 1909 and 1912, and it is quite a sight.

A remarkable woman

Jeanne de Merode was born in Paris in 1853, the daughter of the Marquess of Westerlo and Princess Marie-Nicolette d’Arenberg. She never married, and devoted her life to religion and charitable works. The list of what she built or funded for the people of Westerlo is striking. It includes a carpet factory to provide employment for local women and girls, a church and school in Heultje, and a home for the elderly in Westerlo itself. She was, by all accounts, genuinely beloved.

When her brother Count Henri died in 1908, Jeanne inherited the old castle and was expected to leave for Grimbergen, another property she had inherited. The people of Westerlo begged her to stay. She agreed, and instead commissioned a new castle built almost within sight of her childhood home. The architect Pierre Langerock designed it in a neo-Gothic style deliberately inspired by the late Gothic wing of the nearby Tongerlo Abbey. Four small towers, one large tower, and a bell tower in the form of a crown give it a distinctive silhouette that is part fairytale, part civic statement.

The castle also had its own private chapel, on the altar of which Jeanne kept her most prized possession: the Mérode Altarpiece by 15th-century painter Robert Campin. After her death in 1944, this masterpiece was acquired by the Metropolitan Museum in New York, where it now forms the centrepiece of the Cloisters collection. If you have ever visited the Cloisters, you have seen something that once stood on an altar a few hundred metres from where you are walking.

A complicated 20th century

Jeanne de Merode’s final years were unhappy ones. When German forces invaded Belgium in 1940, the castle was confiscated and converted into a local Nazi headquarters. The Countess was forced to move back to the old castle, where she died in July 1944, just months before the liberation. She left her castle to a monastic order of sisters, who used it as a home for retired priests for nearly three decades.

In 1972, the municipality of Westerlo purchased the building and converted it into the town hall and cultural centre. Today the pond in front, with its fountain and sculptural work by Rik Poot dating from 1995, gives the ensemble a calm, civic dignity. You can walk freely around the grounds. The interior is accessible during normal municipal opening hours.

During the Second World War it became the headquarters of the Germany Army, and then after the war it was a rest home for retired priests. In 1972 the town of Westerlo purchased the castle and converted it into the town hall and a cultural centre. The pond with fountain and accompanying artwork by Rik Poot in front of the town hall dates from 1995. The castle is accessible during normal opening hours.

The route

The full walk is 12 km and follows a clockwise circular route starting and finishing at the Tourist Office on Sint-Lambertusstraat. It is largely flat, passing through the town centre, down to the Grote Nete riverbank, through the Rothoek-Kwarekken nature reserve, around the grounds of Kasteel de Merode, through the abbey grounds at Tongerlo, and back past the castle of Countess Jeanne into the centre.

The route is well-signed and connects into the De Merode walking node network, which means you can extend or shorten it as you like. The riverbank section is particularly well-maintained and accessible. A word of warning: the Kwarekken section can be extremely muddy in winter: waterproof boots are strongly recommended between November and March.

And that was the final stop on this delightful and interesting 12 km. I hope you enjoy your walk around Westerlo. All that remains is to mention that you can download the route and GPX directly from my page on RouteYou, and above is a map of the route with key sights (I walked clockwise):

Any questions on the route, just drop me a line.

Ever wondered what you just walked past?

Three pocket guides to help you identify what you see in the Belgian countryside: from the crops in the fields to the berries, seeds & nuts in the hedgerows.

Farm Crops Field ID Guide

Know your wheat from your barley, your flax from your rapeseed, in the fields you walk through.

Get the guide (€4)

Hedgerow Berries ID Guide

From elderberries to sloe: know what’s in the hedgerow and whether it’s edible.

Get the guide (€4)

Seeds & Nuts ID Field Guide

Identify the seeds and nuts you find along the path or underfoot in the woods.

Get the guide (€4)

Denzil Walton

I created Discovering Belgium in 2011 to share the country’s hidden stories, fascinating places, and remarkable people. Through articles, photography, and audio walks, I share discoveries that reveal Belgium beyond the obvious. Hope you enjoy this site.