Solvay Castle

Château de La Hulpe is a 19th-century mansion set within a sweeping landscaped park in Belgian Wallonia, a short distance south of Brussels. Together with its grounds, known today as the Domaine Solvay, it ranks among the most popular walking destinations in the region and is listed as an exceptional heritage site of Wallonia.

Who built the château, and when?

The château was built in 1842 for the Marquis de Béthune, in a Flemish neo-renaissance style marked by tall turrets and ornate gables. Ownership changed hands several times over the following decades: between 1871 and 1893 the estate belonged to Baron Antoine de Roest d'Alkemade, who extended the grounds southward, adding meadows, the banks of the Argentine stream and the Nysdam ponds to the property.

How did the Solvay family come to own it?

In 1893 the estate was bought by Ernest Solvay, the industrialist who founded the global chemical company Solvay & Co., and it became his summer residence. He commissioned Victor Horta — one of the most influential architects of Belgian Art Nouveau — to redesign the château's interior. The renovation gave the building a more classical appearance, and a front terrace with a glass canopy on cast-iron columns was added. Solvay also reshaped the surrounding park and kept expanding the estate, which by 1920 covered 490 hectares.

What can visitors find in the park today?

The park surrounding the château, nicknamed the "park of a thousand rhododendrons," now covers around 227 hectares of mature woodland, ponds and walking paths. In front of the château lies a symmetrical French formal garden adorned with sculptures. The grounds are also home to the Folon Foundation, dedicated to the work of Belgian artist Jean-Michel Folon, making the estate a draw for art lovers as well as anyone looking for a quiet walk in nature.

How did the estate become public property?

In 1968 Count Solvay donated the entire property to the Belgian state on the condition that it be used for cultural purposes. Since then the Walloon region has managed the site as the Domaine régional Solvay, keeping the park and the grounds around the château open to visitors throughout the year.

Frequently asked questions

Can visitors go inside the château? The interior is opened to the public only occasionally, mostly during cultural events and exhibitions held on the estate — the surrounding park, however, is open to visitors year-round.

Who redesigned the château's interior? The interior renovation, commissioned by Ernest Solvay around the turn of the 20th century, was carried out by architect Victor Horta.

How large is the park today? The park covers about 227 hectares, although at its peak under Ernest Solvay the whole estate stretched across as much as 490 hectares.

What else is there to see on the estate? Besides the château, its ponds and the French formal garden, the grounds host the Folon Foundation, showcasing the work of artist Jean-Michel Folon.