There are multiple lots and the choicest spots are gone at least 2 hours before every show. Your best option is to go to the red rocks website and they have a printable nap of the whole area ( including bathrooms). Personally, I always park and eat in the nearby town of Morrison and Lyft to the drop-off area. Sooo much easier. Red Rocks is the world's best concert venue and the world's worst traffic situation.
Several lots are well marked. As with any venue the close ones fill up first.
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