I lived in Denver for 23 years...went to Bandimere every year for the Mile Highs...I LOVE Bandimere and the Bandimere family...love the site for a track the most.
In all fairness, comparing my new track, Bristol, the parking in Denver is OK. There is plenty of it.
But at Bristol they have PLENTY of trams to take you to your car and the parking is FREE...it's not in Denver.
But you will enjoy the event...the place will be packed...and REALLY, drink lots of water, whether you feel like it or not.