Boil the potatoes in salted water until fork-tender, about 10–12 minutes. Drain and let them cool before cutting into cubes.
In a small bowl, whisk together the olive oil, lemon juice, salt, and black pepper to make the dressing.
In a large mixing bowl, combine the cooled potatoes, cherry tomatoes, cucumber, red onion, olives, and crumbled feta cheese.
Pour the dressing over the salad.
Gently toss until all the ingredients are evenly coated.
Refrigerate for 20–30 minutes to allow the flavors to blend.
Serve chilled or at room temperature, garnished with fresh parsley or oregano if desired.