Bring a large pot of salted water to a rolling boil over high heat. Add the penne pasta and cook according to package instructions, typically around 10-12 minutes, until al dente. Drain and cool the pasta.

While the pasta cools, wash and chop the cherry tomatoes, dice the cucumbers, thinly slice the red onion, and chop the bell peppers. Place in a large mixing bowl.

Once the pasta has cooled, add it to the bowl of chopped vegetables and gently fold the ingredients together.

In a small bowl, whisk together olive oil, red wine vinegar, oregano, salt, and pepper. Adjust seasoning to taste.

Pour the dressing over the pasta and vegetable mixture, toss gently to coat all ingredients.

Crumble feta cheese over the top, add Kalamata olives, give it a final toss, and let it sit for about 10 minutes before serving.