It says on the website only one vehicle is allowed with each reservation and remember it's $15 cash (no cards!) at the entrance per vehicle.
You can only have one vehicle, but what they told us to do was to pay to park both cars at Reimers Ranch about 1 mile down from Hamilton, park one car there, have everyone pile into one car, drive back to Hamilton Pool, and they won't make you pay to park again if you show your parking pass from Reimer's ranch. That worked for us since we could be uncomfortable for a 5 min ride into the parking lot. We got 8 adults in a hyundai Tuscon, lol.
Only one vehicle with up to 8 people.
You have to pay per car is what I recall
No only one vehical
Pay per car
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