Weerde Sluice Tower

Remnant of a medieval lock tower from the last years of the 13th or early 14th century, built on a strong bend in the Zenne. A deed of approval by Duke Jan van Brabant in 1297, of the sale of a water mill by Wouter van Hollaken to Boudewijn van Echove and Daniël Bouchout, mentions the privilege of building a lock on the Zenne; later the Bouchouts became the sole owners and in 1360 the mill with lock was donated by Jan Wijtvliet to the abbey of Grimbergen; around 1500 the latter sold it to the city of Brussels. Until around 1900 the iconography shows a square tower of sandstone, supported by buttresses, covered with a steep tent roof (slate). Today only one facade is standing and the rest is the substructure. Sandstone building covered with ivy in a fairly small regular pattern. At the left arm banks, preserved walls with slots for the lock gates, and water gate: bevelled round arch with profiled stretched cornice over the entire length; in the superstructure, a central Gothic trefoil window, finished with a pointed arch-shaped drip moulding, a square window, scaffolding holes and a profiled cornice. (Wikipedia)

The Sluistoren is a building in the town of Weerde, part of the Flemish Brabant municipality of Zemst, located on the Watermolenstraat.
Source: Wikipedia

The last remains of an old lock tower add value to your passage...