The eight boats in the CGN's Belle Époque fleet possess a unique heritage and tourism value. The renovation of each one requires specialized expertise, both technical and in terms of heritage preservation. This translates to a cost of between 20 and 30 million Swiss francs per boat for a complete renovation.
Between August 2003 and July 2005, the boat "Simplon" benefited from a first partial renovation following the life-saving explosion that marked the beginning of the mobilization to save the entire Belle Époque fleet.
On August 16, 2003, in the harbor of Geneva, a serious breakdown in the boiler room rendered the "Simplon" unusable. The newly formed ABVL, established just a year earlier, mobilized and achieved the remarkable feat of raising nearly 2 million Swiss francs in 18 months. The CGN contributed an equivalent amount to this effort. The work undertaken from May 2004 onwards included the refurbishment of the damaged boiler, the improvement of navigation equipment, and the restoration of some of the interior furnishings.
Between September 2009 and May 2011, following the discovery of cracks on the pistons, the "Simplon" underwent a second partial renovation focused on its legendary steam engine.
The work consisted primarily of a complete overhaul of the steam engine, reputed to be the most powerful and responsive in Europe, as well as the installation of bow thrusters to significantly improve the ship's maneuverability. The exterior was completely repainted during this work, and the hull was sandblasted. The paddlewheel shafts also had to be replaced during the winter of 2020-2021.
The main steps of these interventions were as follows: boiler repair and retubing, complete overhaul of the steam engine, replacement of outdated equipment, installation of modern operating systems, sandblasting and complete painting of the hull, and replacement of the paddle wheel shafts.