Denver has an amazing bike / multi-use trail system.
I have explored some, but definitely not all of Denver’s 650 or so miles of urban bike trails. I am amazed at how well the greater Denver bike trail systems are maintained throughout the year. My commute to work is on a series of 4 trails. The Lee Gulch trail can get washed out during periods of heavy rain.
I have seen large sections get washed away and within 4-5 days the trail is re-built better than before. Yes the Denver area is definitely a bike-lovers paradise; it seems to always be rated in someone's top ten list of most bike friendly cities.
The loop I put together ended up being about 74 miles.