In his welcome-speech, the Lord Mayor of the City of Mainz, Michael Ebling, emphasised the extremely dynamic development of the new Mainz urban quarter: "The development in the Zollhafen is currently very rapid. You can almost see it growing." Ebling continued: "The Rheinallee III building offers exactly what is so urgently required in Mainz – rented flats in an attractive and liveable environment." At the same time, the Zollhafen has also been integrated to a greater extent with Mainz-Neustadt again through the buildings being constructed on Rheinallee and has expanded its infrastructure in a practical way.

Dr. Ralf Schneider, Group Head of Development at CA Immo: "Rheinallee III is a key project for the Zollhafen. The spacious REWE supermarket on Rheinallee will become the local shop for the quarter and the surrounding area. The seven-stream daycare centre will make it easier for families to combine work and homelife in the future." This is yet another example of how it’s possible to implement the desired mixed use of living and everyday facilities in the Zollhafen.

The residential and commercial building on Rheinallee in Mainz will also, in particular, house 181 one- to four-room apartments in the future, in addition to the supermarket and the day nursery. The architecture of Rheinallee III comes from the offices of Römer Kögeler und Partner Architekten in Cologne. A defining feature of the design, alongside the clinker facade, is the spacious, partly split-level ground floor. The building has an underground car park with 247 parking spaces for cars, 94 of which can be used for retail. The supermarket will include a bakery and another store in addition to its own range. Alongside the construction of the building and the renting of the retail space, CA Immo is responsible for the nursery lease. The renting-out of the flats will be undertaken by Aberdeen.