According to this theory, the walls of the original hermitage were coated in a mixture of crushed tiles and bricks to make them waterproof,[2] which produced the characteristic red colour.

The foundation was confirmed in 1373 by Gérard de Dainville, Bishop of Cambrai, and the following year, was affiliated to the order of Canons Regular of Saint Augustine.

In 1381, construction of the church was initiated, after receiving gifts of land and lakes from the Duchess of Brabant, as well as privileges and tax exemptions.

Springs were plentiful in the area, the ponds supplied fish, and a water mill on the stream was used to grind grain and press oil.

The white sandstone church is decorated with paintings from Peter Paul Rubens' studio, and in the 16th century, the monastery was one of the most prestigious in the Spanish Netherlands, in large part due to its proximity to Brussels.

Charles V, the Holy Roman Emperor, Albert VII, Archduke of Austria and Isabella of Spain all stayed there, as well as many other notable personages.