No, You don't have to buy tickets, but there is a fee to enter and you also have to make a reservation online in advance or else you're not allowed to go right now due to covid restrictions and obviously the heat wave. You sign up for your 1-hour swim session and then you have to get out at the end of that hour but the pro is that the pools are not crowded at all because of the limited access
You have to sign up and pay the entrance fee ahead of time on the website. There are no tickets. The employees have a list of people who are signed up and they let you in at the gate. It's easy and convenient.
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