Letecká 100 (Aviation Hundred) is a 106km loop ultramarathon starting and finishing in Trenčín, Slovakia, with 3,590m D+ over forest ridges in the Považský Inovec and Strážovské vrchy ranges. The race is a WSER qualifier (sub-21h finish required), carries 4 ITRA points, caps at 250 participants, and sells out the same day registration opens in November.
At 9.5% DW average uphill gradient (rank 281/390 — bottom 28% steepest, gentler portion of the DTR database) and 34.8% flat terrain (rank 208/390 — above mid), this is a highly runnable 100km+ course with an unusual 16km flat opening along the Váh River dam before the first climb. The biggest single ascent (600m, rank 197/390 — just above mid) arrives back-loaded at km 68. March makes this a genuine winter ultra — snow, mud, and ice are possible. EUR 82 entry (~EUR 0.77/km). Bratislava BTS and Vienna VIE both 78 minutes away. Not IS FAR. 202 finishers from 243 starters in 2025 (17% DNF). Next edition expected March 2027.