National Basilica of the Sacred Heart

The National Basilica of the Sacred Heart in Brussels is one of the largest churches in the world and the defining landmark of the Koekelberg district, which is why it's often known simply as the Koekelberg Basilica. Its massive brick-and-reinforced-concrete structure, crowned by a green copper dome rising 89 metres above the ground, dominates the northwestern skyline of Brussels and is visible from many parts of the city.

Where did the idea for the basilica come from?

Back in the mid-19th century, King Leopold I dreamed of turning the then-uninhabited Koekelberg plateau into a royal residence. After his death, his son, King Leopold II, imagined something different: a Belgian pantheon honoring the nation's great figures. The turning point came in 1902, when Leopold II visited the construction site of the Sacré-Cœur basilica on Montmartre in Paris. He decided Brussels deserved a comparable monument, linked to the city centre by a grand boulevard modeled on the Champs-Élysées.

How long did construction take?

Leopold II himself laid the cornerstone in 1905, with the entire project conceived to mark the 75th anniversary of Belgian independence. Construction, however, stretched across several decades and was interrupted twice by the two World Wars. The basilica wasn't finally completed until 1971 — more than six decades after the first stone was laid.

Why is its architectural style so unusual?

The original design, by architect Pierre Langerock, was Neo-Gothic. After the First World War, the whole concept was reworked: architect Albert Van Huffel took over the project, and together with Paul Rome gave the building its distinctive Art Deco form while retaining elements inspired by Neo-Byzantine architecture. This blend of two stylistically distant traditions makes the basilica look unlike any other great church in Europe, and it remains a subject of debate — some consider it an architectural masterpiece, others a controversial experiment.

How big is the basilica?

The building measures 89 metres in height and 167 metres in length, covering roughly 8,000 square metres. These dimensions place it among the largest churches in the world, with many rankings listing it as the fifth-largest. The silhouette is defined by two slender flanking towers and an almost equally tall central green copper dome, which has become one of the symbols of this part of Brussels.

Frequently asked questions

Where exactly is the basilica located? In the Koekelberg district in northwestern Brussels, set on a hill visible from many vantage points across the city.

Who initiated its construction? The idea for a grand church on the Koekelberg plateau originated under Leopold I, and it was his son, King Leopold II, who acted on it after visiting the Sacré-Cœur in Paris in 1902.

Why did construction take so long? Work that began in 1905 was interrupted by two World Wars, and a shift in architectural concept from Neo-Gothic to Art Deco further delayed the project — the basilica was finally finished in 1971.

How does it differ from other great European churches? It combines Art Deco forms with Neo-Byzantine elements, making it stylistically unique compared with the classic Neo-Gothic or Baroque churches of similar scale.