The Tommenmolen is one of the five water mills on the Maalbeek in the Flemish Brabant municipality of Grimbergen.
This 16th-century mill (1541 or 1547) houses exhibitions from the Museum of Old Techniques (Het MOT).
The mill that is now called the Tommenmolen was originally called the Liermolen. Around 1400 it was given the name Tommenmolen after the Van der Tommen family, who owned it for more than a century. The Tommenmolen was probably built after the first Liermolen was donated to the abbey. In 1573 the Norbertines of Grimbergen bought the mill and it remained in their possession until the French occupation.
During the religious unrest in the 16th century the mill fell into disrepair. In the 18th century the mill was also in need of repair. The external drive was renewed in 1930 and the mill remained in operation until the 1960s. The mill was purchased by the municipality in 1967 and partially restored in 1971. The water wheel could be set in motion but it was no longer milled. In the meantime, the locks, the water wheel and the interior have been restored.
A half-timbered barn and a baking oven were placed on the grounds of the Tommenmolen, which had to disappear elsewhere in Grimbergen. The baking oven was completely rebuilt in 2016 and is used for various baking activities. Next to the barn, the MOT placed a metal horse mill, a so-called "manège" with which, for example, a threshing machine can be driven.