 If you crave a change of environment, a day's outing to Formentera offers the bonus of a sea voyage.
You can get a bonus sea voyage with a day's outing to Formentera.
mnli hypothesis: You can get a bonus sea voyage with a day's outing to Formentera. premise:  If you crave a change of environment, a day's outing to Formentera offers the bonus of a sea voyage.