Go to the south beaches of menorca. The water and beaches are great over there. Port of mahon is good for restaurants and having lunch. Be aware of the environment and nice houses. To float out of the port will take you approx 45 minutes. Then go right to the beaches
Menorca is just the best. Especially Es Grau with Isla d'em Colom is unbeatable in terms of nature and authenticy. The beaches there are among the best on the entire island of Menorca. In July and August it becomes quite crowded also here, so best in June, September and October