the rail line from horberg to nordegg is at least 6hrs one way [ best case ] i have done it in 4.5 but there was frost in the mud and skeg....
a good ride is from saunders [ down the last part of the rail line ] to nordegg then up to the top of mount baldy [ 8900 feet at the top and can see everywhere ] and then back...
Around the crowsnest the trails can go for a long long ways.
The plane crash trail side of the highway has tons and the Atlas side as well. You can get a map at the local stores in the area and they show the gret multitude of trails in the area you can ride.
Cadomin has a few medium/long trails but some connect by travelling the gravel road so that changes things.