Major Events and Mountain Bike Tours
There is a vast multitude of multi and single day bike tours offered through reputable organizations across the US. When sorting them out, look for well defined, time tested routes. It will be easier than you think to find clear maps with interesting points of views listed.
Start with https://www.adventurecycling.org/adventure-cyclist/online-features/top-10-mountain-bike-tours/, or give REI a look here: https://www.rei.com/adventures/trips/mountain-biking
If striking out on your own is more of your thing, this is a great place to check things out:
https://www.nationalgeographic.com/adventure/lists/biking/best-mountain-biking-towns/ or https://www.mtbproject.com/featured/featured-rides/highest-rated or the UCI web site http://www.uci.org/mountain-bike
