Other masters named were Heinrich Schönbel (Henrich Schoinboil), Arnold von Lieser (Arnolden van Leser) and Johann Meyener.
[1] The outside tower walls used to be plastered and coloured with a whitish to dark yellowish (ochre) paint to underline the architectonic structure.
There are indications of this in the detailed master builder's accounts of this period, which have been handed down, about lively building activity on a new tower of an unnamed position.
Despite a strained financial situation, the funds were raised by the citizenry, i.e. not only by the ruling class, but by a large number of the citizens, deliberately without a contribution from the reigning Cologne Archbishop Dietrich II of Moers.
Because of the political and financial pressure the archbishop was under (including the mortgaging of the city, Soester Fehde 1444-1449 and others), the timing was favourable in this power vacuum.
In addition to the right to live with his mother, two wagons of firewood and the clothing of a town servant, he received a Goldflorin salary per year.
Several hook rifles, field snakes were placed on the upper floors or on the battlements, and other defensive material (oil, pitch, stones, powder) was stored in the rooms.
In the night of 30 April to 1 May 1689, the tower withstood an attempted blast by the retreating French troops of Ludwig XIV, thus demonstrating its stability.
In 1880, major renovation work was carried out, and the old city coats of arms made of tuff were replaced with new ones, although they were inserted vertically instead of at an angle and unpainted.
On the occasion of the anniversary, a special exhibition "550 Years of the Round Tower" was held in the City Museum from 18 May to 7 December 2003, and a booklet in glossy print on the subject was published.