Cave of the Winds tours sell out before 9 AM on holiday weekends.

If you roll up after 9 AM on Memorial Day or Fourth of July, you’re probably not getting in.

The tours run first-come, first-served and the slots fill fast. Holiday weekends bring crowds that start lining up at opening (usually 8 or 9 AM). By 10 AM, the next available tour might be late afternoon—or gone entirely. I’ve seen the early tours sell out before the ticket booth even opens.

The smart move: arrive 30 minutes before opening. Bring coffee. Don’t bank on “I’ll get there by noon.”

Set an alarm.