The Wendlingen timber parking garage is the only and largest circular — convertible and type-pure dismountable — timber parking garage in Germany, possibly worldwide. Located between the future OTTO Quarter and Wendlingen station, the five-storey building offers 349 parking spaces, 200 bicycle spaces, e-charging, and serves as a Park+Ride hub for the Stuttgart region. Its oval shape maximises efficiency on a constrained site. Built primarily from cross-laminated timber ceilings and glulam columns, it reduces CO₂-intensive materials such as steel and concrete, with prefabricated elements enabling efficient construction. Following circular economy principles, most connections are screwed or plugged, allowing easy dismantling and material reuse. A translucent glass façade to the north provides noise protection, while the open southern façade showcases the timber structure and greenery. A green roof and photovoltaic system enhance sustainability and support e-mobility. A sponge-city rainwater concept — green roofs, façade greening, infiltration and permeable surfaces — retains rainwater, promotes groundwater recharge, improves flood resilience and supports a healthier urban microclimate. Thanks to generous clear floor heights and a column-free layout, the building can be converted into residential or office use if the garage is underused or a change of use is desired — incrementally, floor by floor, keeping it in use and within the material cycle as long as possible.