The drilling rig, built by a Berlin company in 1891, was originally intended to explore coalfields. A spring was drilled at a depth of 300 meters, which ejected saline water under high pressure. Analysis revealed the water to have healing properties; its composition was roughly equivalent to that of the famous Wiesbaden Kochbrunnen fountain. Subsequently, a company called "Krefelder Sprudel GmbH" was founded, which purchased the drilling rig from the construction company for 15,000 marks. This wooden drilling rig has since become the most distinctive component of the facility. It stands in the center of the main wing above the borehole. The structure consists of four massive round timbers firmly anchored in the ground and braced together by beams. The drilling rig, shaped like a truncated pyramid and covered with clay roof tiles, tops off with a slated roof hut with a gable roof. The piping and the old drilling winch are still in place today, as is the stone-lined spring beneath the drilling rig.
Krefelder Sprudel GmbH established a large distribution network for the sale of bottled sparkling water. It could also be consumed directly on site on the terraces and in the adjoining rooms of the tourist restaurant, which offered a view of the bottling room. The commercial and residential buildings of the complex are built in log cabin style with brickwork, some of which is half-timbered.
In the early 1960s, the spring dried up. The Sprudelturm (sparkling tower) was preserved as a technical monument of high architectural and urban significance.
(Source: Krefeld Architectural Guide 1996; pages 336 and 337; self-published by the City of Krefeld, Planning Office; ISBN 3-9804181-4-6)
Today, the repeatedly expanded tourist restaurant houses the Greek restaurant "Zeus."