25k Sulphur Springs Trail Run

I do a fair bit of my training on a treadmill in our dining room/home gym.  I know some people hate treadmills, but I really don't mind them.  With the family, work etc, it makes getting workouts in possible for me as I can do it before the sun comes up or after it has gone down.  I like the numbers feedback and find it pushes me (I can't just slow down without pressing the button to slow it down).  I'll even go as far as saying I think it builds mental toughness required to do these 'endurance' sports I'm leaning towards the last few years.
But put me out on a trail, and it takes me to a whole other world!  It is the pinnacle of running! It's an experience for all the senses. I may not stop and smell the flowers, but the freshness is in the air.  I hear the birds sing and the crunch of leaves underfoot.  I feel the heat of the sun or raindrops or wind on my face.  I see vibrant colours, beautiful scenery and sometimes some wildlife.
Many of the races I've done have had some off-road portions, but the Sulphur Springs race was my first real (absolute) trail race.
And man, it was a tough course.
2 things I thought about a lot out on the trail while my senses were enjoying themselves were:
1) how it was a very good decision to drop down from the 50k to the 25k, as I quickly came to realize 25k on this course was much more than 25k on any other course I'd ever raced on.  There were some significant, steep long climbs; and even the descents are hard on the body.  To give an idea I was approximately 15 minutes slower during this 25k then I was doing 30k this year in Around the Bay Road Race (also a hilly course); and
2) how incredible the people out there were taking on 100 miles.  They had to do the 20k loop portion 7 more times than me... I was awestruck!
And that's what plants the seed... This was the first time I'd actually witnessed the ultra marathon taking place; I'm certainly intrigued!
I look forward to doing more trail races and maybe one day really committing to some kind of ultra running feat.