Start by cutting the cold watermelon into medium-sized cubes, placing them in a large mixing bowl.

Wash the cucumber thoroughly and slice it into half-moons or quartered pieces, then add it to the bowl with watermelon.

Crumble feta cheese generously over the mixture and sprinkle in the chopped mint leaves.

In a separate bowl, whisk together olive oil and lemon juice until emulsified.

Drizzle the dressing over the salad, gently tossing to combine without mashing the watermelon.

Allow the salad to rest for about 5 minutes before serving.