There are three main water parks in Istanbul with Aqua Club Dolphin in Esenyurt, Aqua Marine in Buyukcekmece, and Marina Aquapark Waterland in Tuzla. The Eser Diamond Hotel in Silivri also has a couple of slides and can be a decent budget-friendly option.
Intro
In general, the water parks in Istanbul are not world-beaters of any sort, but they can satisfy the needs of the average tourist.
Aqua Club Dolphin


At a distance of 30 km, Aqua Club Dolphin in Esenyurt is the closest water park to Sultanhamet and Taksim. It’s also the most popular and the biggest around with four large swimming pools and five on-site restaurants.
Tickets
70₺ for men / 60₺ for women / 35₺ for children with those under 5 being free. On Sundays, the price goes up to 80/70/40₺.
Add roughly 30-40₺ if you’re a tourist and not a local.
Aqua Marine

The Aqua Marine in Buyukcekmece is smaller in size and a little farther away (45 km) from central Istanbul. It has three big swimming pools and an assortment of slides and water games.
Tickets
70₺ for men / 60₺ for women / 35₺ for children with those under 5 being free. On Sundays, the price goes up to 80/70/40₺.
Add roughly 30-40₺ if you’re a tourist and not a local.
Marina Aquapark Waterland

While it claims to be the largest, we would have to say that Marina Aquapark Waterland in Tuzla seems smaller than the others. It does, however, have the best view as it’s right on Sea of Mamara. This is about 50 km from central Istanbul and while they’re a lot of slides and options, they’re all bunched quite close together.
Tickets
65₺ for teens and adults / 45₺ for children 4-12 with those under 4 being free. On weekends the teen/adult price goes up to 85₺.
Add roughly 30-40₺ if you’re a tourist and not a local.
Eser Diamond Hotel

While not a true water per se, the Eser Diamond Hotel has a decent sized water slide and 3-lane toboggan slide. Considering the price of the hotel stay can be cheaper than a day out with the kids at the main water parks, it’s definitely worth a look for those who are budget conscious.
Tickets
Free for hotel guests.
Map of Water Parks
You’ll find all three water parks marked on interactive map below. When including the Eser Diamond Hotel, three of them are located on the European Side of Istanbul, while Marina Aquaupark is the lone park on the Asian Side.