Upon driving up the road towards the Jangbok tunnel, I came to notice a waterpark in Jinhae. After speaking to my students about their summer vacations, I have confirmed its name: Sun Beach. It is where Parkland amusement park once was. Anyways, I can’t promise it is amazingly awesome but it is outdoor swimming in the Changwon area and has a wavepool for what that is worth!
Here is a Korean article about it. It seems to be about 12,000 won and open from 9 AM – 8 PM until mid-September.
Bus Numbers that go here: 150, 160, 162, 163, 163, 164, 751, 760, 762