On September 1st 2025, the grand opening of De Kelder took place. For years, Data Science Association (D.S.A.) Pattern has been arranging its own memberspace with bar. Starting in the year 2019-2020, Board 3 of this Association came up with the first plans to move from the old memberspace in Metaforum 3.062 (called The Pattern Room) towards something new. The Pattern Room was given as a gift by the faculty of Computer Science and Mathematics during the founding of D.S.A. Pattern, just to stay for a few years until D.S.A. Pattern could move to somewhere else. Moving on campus takes a lot of time and effort, therefore work continues on it with Board 4, 5 and the Neuron Taskforce (a group of people working on moving in their spare time) from 2020 to 2022. During these years, options were looked into where to move to on campus. After lots of research and conversations, there was only one perfect option where a new memberspace could be built, it was the basement (de kelder in dutch) of Neuron. Neuron itself didn’t exist at that time but the building was there and called Laplace. There were plans for a long time to renovate it and in 2023, Neuron opened its doors without a new memberspace for D.S.A. Pattern. The decision, made at the last minute and involving numerous stakeholders of D.S.A. Pattern, came as a surprise to many within the association who were working on the move. Board 6, 7 and the Neuron Taskforce worked very hard on getting a new memberspace either in Neuron or somewhere else, with Februari 2024 being the month of getting greenlight for a new memberspace with bar in Traverse. Last year, Board 8 and the Member Space Moving Committee (MeSMoCo) worked hard on realizing what D.S.A. Pattern wanted for years. After 6 years, the grand opening of De Kelder took place with a week's worth of celebrations and can be seen as one of the most important occasions for D.S.A. Pattern to date.