Somthing else that might be of some help.Ultra Running magazine has lots of race reports and results, where they give a 1-5 score for trail conditions and 1-5 for vertical gain.
http://www.ultramarathonrunning.com/races/usa.html#WI
Most sources are missing so many races
Where is the Chilly Chippewa 50k, John Dick Crusty 50k, Keyes Peak 50k, T-Bunk Endurance CHalleneg (50k, 50M, 100M, 150M, 200M), the 6 hour race in Green Bay, The 8 hour trail race in Hartford WI, the 6 hour race at Goose Island (La Crosse), the Glacial Trail 50k/50M, The Frozen otter 100k
So the above source has 6 races and I count at least 9 races missing ... maybe more?
Dances With Dirt Devill's Lake 50k/50M
The big 4-0 Eau Claire
Ice Box 480 (8 hour) River Falls)
NorthFace 50k/50M
So I count 19 total ultras in WI and
http://www.ultrarunning.com/calendar.html
This source picked up 13 of them - with the terrain / elevation (1-5) so better than the 1st one I looked at
Long dead ... But my stench lingers !
Another vote for Dirty German 50k. It was my first ultra this past May and it was a great race. Good first trail 50k, as the park is not too technical or hilly, so it will ease you in.
Another source you should consider:
www.traildawgs.org
They are based in Delaware and put on some amazing races. The Delaware Triple Crown and Trail Marathon (while not ultras) are awesome races to consider for the spring.
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