Place Guillaume II, known locally as the Knuedler, is the central square of Luxembourg City, covering an area of more than 9,250 m². Between 2020 and 2023, the square underwent a complete refurbishment: new paving, new tree pits, a playground, new lighting, a fountain and a modernised entrance to the LCTO tourist office. Architect Arlette Schneiders designed the concept, commissioned by the Ville de Luxembourg. The works were carried out in seven phases to allow the hospitality businesses and the weekly market on the square to continue as far as possible, and were completed in spring 2023.

As part of that refurbishment, the square was planted with new, large plane trees. Van den Berk Boomkwekerijen supplied Platanus x hispanica 'Malburg' with a trunk girth of 70 to 80 centimetres. Because of the size of the trees and the narrow historic streets of the city centre, the transports travelled to the centre at night, using specially extended transport under police escort. Existing plane trees that could not be returned to their original location were replanted elsewhere in the city at the time.

Plane trees tolerate paving and air pollution well, and their large leaf surface captures fine dust. Their eventual size means they cannot be planted everywhere in the city centre. Here, there is room for them: the crowns provide shade over a large part of the square, reduce temperatures on hot days and break up the otherwise largely paved space with visible greenery, contributing to the well-being of residents and visitors to the city centre.