Today, the StadlerRail "Flirt 3" "Traverso" RABe 526 102/202 of the Südostbahn (SOB) made test runs on the Gotthard mountain south side, in the Leventina, between Airolo and Bodio. The train is on the Pianotondo viaduct in the uppermost level of the "staircase" of the Biaschina. From December 2020, these trains will travel between Zurich/Basel and Locarno via the Gotthard mountain route in cooperation between the Südostbahn and the SBB.