At the heart of the old village of Diegem, near Brussels, stands a remarkable church tower crowned by a unique stone spire. Unlike most spires of its time, which were made of wood and covered with slate, Diegem’s spire was constructed entirely in stone—a decision that required extraordinary time, patience, and craftsmanship.
For twenty years, skilled stonemasons worked meticulously on the spire, which eventually became an outstanding example of Brabantine Baroque architecture, almost folkloric in character. Its layered structure, carefully filled with stone rubble, ensured exceptional durability. The local stonemasons, renowned for their expertise, used the region’s hard, white natural stone, the same material employed in notable buildings such as Ter Elst Castle.
War and Reconstruction
During World War II, the spire faced destruction. In 1943, the German authorities deemed it an obstruction to flight operations at the nearby Melsbroek airfield and ordered its demolition. Thanks to heritage authorities, the spire was carefully dismantled instead. Each of the approximately 5,000 stones, weighing a total of 230 tons, was numbered, photographed, and lowered systematically. The dismantling took thirty days and cost 135,000 francs—a modest sum considering the scale of the operation.
Eight years later, on April 2, 1951, reconstruction began under architect De Groodt and the same contractor. The work was completed on October 14, 1951, at a cost of 732,000 francs. Alongside the restoration, several improvements were made: a wooden spiral staircase was replaced with a concrete one, and a new tower clock was installed. Following tradition, the gilded weathercock was carried through the village before being placed atop the spire, where it now rotates on two glass marbles.
Today, the people of Diegem can take pride in this rare stone spire, often compared in shape to a Chinese pagoda. Its historical and artistic value has earned the church the status of a protected monument—a testament to the village’s rich heritage and exceptional craftsmanship.
Good to know
Other sources speak of 35 days for the dismantling, carried out by the contractor Florent d’Hulst of Lier. For the rebuilding, architect De Groodt worked with architect Julien De Ridder. At the end of September 1951 the cross and cockerel returned to the spire, and on 28 October 1951 the whole of Diegem celebrated with a parade, new bells, a new tower clock and fireworks.
Who built the spire?
Before 1654 the tower had a Brabant tent-shaped roof. The new spire is octagonal and 29 metres high. On the first gallery are four inscriptions, hidden behind the clock faces until 1951: on the south ‘Erigebar anno Domini 1654’ (I was raised in 1654), on the north a chronogram naming Cornelius before Catherine, on the east parish priest Joannes vander Eycken and on the west lord Gerolinus Oudart. The architect's name is not there; for a long time Lucas Faydherbe was thought to be the builder.
The answer was in the church accounts of 1655-1657: a payment of 30 Rhine guilders to ‘Sr Mercx, ingenieur ende architecke van syne majesteit’, for his work on the new tower. Petrus Paulus Mercx was a pupil of the architect Francquart. He worked on the port of Ostend, on the course of the Senne in Brussels, on triumphal arches (1670) and on the fortifications of Brussels (1672). He became architect and engineer to the king and to the city of Brussels, and died there on 15 March 1685. His spire represents the papal tiara of Cornelius: the galleries are the crowns, the windows the gems.
The tower was repaired in 1769 (for 993 guilders) and in 1887, when French stone from Joli-Bois was used. It used to be climbed by an outside staircase, in the corner where the sacristy has stood since 1775. Tower visits at Easter stopped in 1971, when television aerials were put up on it.
Light and aviation
Since 1951 the tower has been floodlit at Easter. In 1952 the contractor d'Hulst fitted ladder rungs up to the top for an aviation beacon, and in 1972 sodium floodlights were installed around the church and the castle, for about 400,000 francs.
In January 1960 demolition threatened again: the Airways Authority planned a longer runway, with the church exactly in line with it. Diegem resisted. A committee led by mayor Mommaerts, with all the parties and the parish priest, even polled Sabena pilots: of the 76 who answered, 57 thought demolition unnecessary. The Royal Commission for Monuments refused, and a compromise was reached: the runway was turned a few degrees and a red light was placed on the tower cross.