Where to swim near Istanbul — Black Sea, Sea of Marmara, or Princes Islands?

Black Sea beach entry costs 650 lira on weekdays and 850 lira on weekends, according to a recent visitor.

Getting to the Black Sea beach takes about 2 hours (metro + bus), but the route runs along the Bosphorus with scenic views and cozy villages.

At the Black Sea beach, free sunbeds run out by 10am and seaweed can be felt near the shore. Food has queues but is quickly restocked; wifi and safe are free.

For swimming trips to the Princes Islands, taxis are overpriced since you'll switch to a ferry anyway — better to just take public transport to the pier.

The Black Sea runs warmer than the Sea of Marmara in summer, making it the better choice if you actually want to swim.

Princes Islands beaches charge 800–1000 lira per person just to use the beach. Water temperature is around 19–20°C — similar to the Baltic Sea in summer — so swimming is not for everyone.

Şile beach on the Black Sea is a solid day trip from Istanbul. Take a bus from Üsküdar — about 1.5 hours. The water is noticeably warmer than the Sea of Marmara.