Ray (webmaster) on 10/11/2021 4:50:10 PM:
Yes actually it is super-easy, I've ridden it a few times. Where highway 64/40 crosses the Katy Trail, a ramp circles up to highway level and leads to the bridge crossing. It's all very safe; the bike/pedestrian lane across the bridge is completely separated from traffic by a wall, and offers some nice views of the Missouri River.
Once you get across the river, you are in Chesterfield and intersecting the Monarch Trail, with the "Premium Outlets" mall right in front of you. Go right on the Monarch Trail to ride alongside Spirit of St Louis Airport, or go left to ride behind the athletic fields to the "Chesterfield Outlets" mall and Top Golf area. If you want to go deeper into Chesterfield and St Louis County, I can't really offer advice beyond this trail.
More info on this page: https://bikekatytrail.com/monarch-levee-highway-64-bridge.aspx
Good luck and happy trails!