From the Rhaetian Railway -
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As part of the 175th anniversary celebrations of the Swiss railways, the Rhaetian Railway (RhB) is undertaking the official attempt to run the longest passenger train in the world on Saturday, October 29, 2022. The 1910 meter long train with 100 carriages is to roll on the UNESCO World Heritage route Albula/Bernina from Preda to Bergün and further over the Landwasser Viaduct. The corresponding tests for technical feasibility and guarantee of security have taken place in the past few months.
The longest passenger train in the world is to be made up of 25 multiple-unit trains of the latest “Capricorn” type. "
If you're not there there will be a live stream on blick.ch
https://www.rhb.ch/en/news-events/official-world-record-attempt#highlights