Since 1998, parts of the Lettenviaduct have been open to pedestrians and cyclists, and in 2003 the extension to Josefstrasse was provisionally opened. In 2008, the civil engineering office of the city of Zurich (TAZ) began to lay the final surface of the path from a covering of concrete slabs three meters wide. The renovated pedestrian and cycle path was opened to the public in autumn 2009.
The viaduct arches under the pedestrian and cycle path have been used as warehouses and partly for shops and restaurants since the early 19th century. But at the end of March 2003 they had to leave their premises because the viaduct was in need of renovation after more than 100 years of operation, which meant that the fixtures had to be removed.
In the early summer of 2004, the Swiss Federal Railways (SBB) and the city of Zurich found the solution for the new use of the viaduct in an architectural competition. The winning project by the EM2N Architekten AG consortium and Zulauf Seippel Schweingruber landscape architects was based on the simple coach house that existed before the conversion. Because the implementation of such projects is not one of SBB's core tasks, it entrusted the implementation to the PWG Foundation, which wanted to accommodate different, quarter-related uses in the arches.
The PWG Foundation created a new concept under the IM VIADUKT label to make the 53 arches usable again as shops, studios, restaurants and social facilities. The first shops opened on April 1, 2010. The first market hall in Zurich was built on Limmatstrasse where the Wipkinger and Letten viaducts separate. It was handed over to the public on September 4, 2010 together with the other installations. The complex construction work on the listed building took almost two years.