Ran alone and unsupported from Silkeborg to Aarhus. 83k including detours.
The bridge over the railways north of Skanderborg is being renovated at the moment, so I had to take a detour through several raspberry bushes and a stinging nettle field. Ouch!!
I got a little lost along Århus Å, where I accidentally came to the wrong side of the river. It again cost a trip in the stinging nettles and I had to wade across the creek to find the correct path.
The route is really well signposted from Silkeborg to approx. 44k / 36k and again from approx. 55k / 25k to Aarhus. A few minor changes without significance. No signs on the intermediate stretch through Skanderborg = GPX file is a necessity.
Surface: Primarily gravel road, gravel path and asphalt. A bit of a single track with many roots near Silkeborg and muddy paths in Jeksendalen.
Shoe choice: No need for trail shoes. I ran in an old pair of Hoka Clifton 7.
Well-known places where you can refuel water on the go: Silkeborg Station approx. 0k / 80k (opens at 5:00 am); Slåensø approx. 12k / 68k (very clean lake - no filter needed); Knøsgården approx. 15k / 65k; Øm Kloster approx. 32k / 48k (Museum, check opening hours); Alken ca. 41k / 39k (public toilet); Skanderborg ca. 50k / 30k: Slotskirken, public toilet in the city center and the train station; Harlev Mølle approx. 65k / 15K (Arhus Å (small stream) - use filter). Most places are closed in winter.