A project located near to the city of Yekaterinburg in Russia. The design is diving centre in a former talc factory that was in the heart of a industrial town. It builds upon the theory of the liminal transition that also occurs in the sea, where it is called the thermocline. This natural rapid shift in temperature created an in-between state which I explored further as a liminal period. With the design, this liminal experience is physicalized into a diving centre within an old factory on the threshold between a transgressive industrial town and a deserted, now flooded, talc quarry, with the intention to let people learn how to scuba dive before they can experience all the relics on the bottom of the quarry. With the use of materials found on-site, algae that form within the filtration systems of the pools and the structure of the existing factory, the design creates an experience with a mix between artificial and natural and is rather a passing through station then a end destination, therefore staying on the limen, or, treshold.