Swimming across the Gibraltar Strait is a remarkable feat, but not one to be taken lightly. The challenge lies not just in the distance, which is roughly 20 kilometers, but also in the strong, unpredictable currents and the busy shipping lanes. You also have to factor in the water temperature, which can be quite cold even in summer. Without proper training and preparation, this swim can be extremely dangerous. Therefore, it's not just about strength, but also about endurance, adaptability, and careful planning.