Wow!! Need I say anymore about this tour!! Derek was the perfect guide for our tour! We booked this because of the great reviews from other people. I can tell you that the reviews are completely accurate. Derek is an expert in his field and is a great person to spend the day with. We were able to see all the tourist sites, walk up to see Old faithful with very little wait, take several hikes to some beautiful unknown sites, see active wildlife (bison, elk, moose, grizzly bear and a wolf), have a great picnic lunch on a quiet river and take an interesting hike (on a snow covered trail) to see a beautiful falls. Oh yeah, he knows where all of the clean bathrooms are in the park.( As we get older that seems to be very important) This trip is definitely worth the money! This is definitely the best way to see Yellowstone National Park!! Thanks Derek!!