Mountain biked this over a 2-day period. It was a fun journey. Definitely intermediate to challenging. Had some terribly soggy/muddy conditions to work through on the second day. I gave it one less star because there was some trail signage confusion that almost caused me to get very lost and there were sections knocked out that we had to haul our bikes around in some very slippery terrain.
This is a great ride! They have many different distances that are all well supported. My only critique is that they don't hand out medals at the end. :)