I plan next weekend (May 4) to hit the Three Mile Creek trailhead three miles up Guanella Pass Road from Grant, Colorado.
Is it open yet? At least 3 miles north from Grant, Colorado to the trailhead at 9,000'.

I am reasonably sure that is a year-round parking lot. In fact, I've used that parking lot most months of snow season. Note, however, that parking at this lot is VERY limited, so arrive early!

Like Sarah said, open all winter. One time after a heavy snow in winter I recall having to bust through a snowbank created by the snowplow clearing Guanella Pass road, but besides that I've never had issues.

The true winter closure is many miles further north on Guanella Pass road, close to Duck Lake.

Thanks. The problem is that we won't arrive until say at least Noon. What other options for parking might we have, or do we have to bail out??? If we do, we can always go to Hoosier Pass on our way to Vail.