Hiji waterfall - Okinawa

Hello, my wife and I are traveling to Okinawa in March, 2024 and plan to hike to Hiji Waterfall on the 14th. Is there a reservation system for this hike/park or do we just show up and pay the entrance fee on the day we wish to see the waterfall? For context, some parks in the US have a cap on how many visitors are allowed per day. Thank you for the help.

Hiji Waterfall has no caps and does not require reservations. The practicalities are explained here:
https://www.japan-guide.com/e/e7120.html