The National Basilica of the Sacred Heart is a Roman Catholic Minor Basilica and parish church in Brussels, Belgium. The church was dedicated to the Sacred Heart, inspired by the Basilique du Sacré-Coeur in Paris. Symbolically King Leopold II laid the first stone of the basilica in 1905 during the celebrations of the 75th anniversary of Belgian independence. The construction was halted by the two World Wars and finished only in 1969. Belonging to the Metropolitan Archbishopric of Mechelen-Brussels, it is one of the ten largest Roman Catholic churches by area in the world.
Located in the Parc Elisabeth atop the Koekelberg Hill in Brussels' Koekelberg municipality, the church is popularly known as the Koekelberg Basilica ( or ). The massive brick and concrete reinforced church features two thin towers and a green copper dome that rises 89m above the ground, dominating the northwestern skyline of Brussels.