The classic locations are the marshes along the east side of Cherry Creek,
south of "12 mile Picnic area". The marshes extend far upstream, but Virginia
Rail can often be heard within a quarter mile of the parking lot at 12 mile.
Sora can be there too.
SORA has been reliable at marshy area just east of Pelican Point,
which is an eBird hotspot.
That whole marshy and wooded area south of Pelican Point
is the "Wetland Preserve" with its own hotspot, and several VIRA
have been heard there this summer.
Not hard to answer this kind of question by using eBird:
Go to "Explore"
Look under "Species Maps". Enter "Virginia Rail" or just "VIRA" and the name pops up.
search June and July, current year
location: "Arapahoe County"
and zoom in to Cherry Creek SP.
You'll see lots of Personal Locations and a few hotspots where VIRA have been this summer.
Good luck and post to eBird.
Thanks,
Joe Roller, Denver