Just a good clear water for this type of activity.
Fujifilm FinePix XP30 10/3000s, f 6.2, ISO 100, 5 mm
License: CC0 Public Domain
Ron Sanderson has released this “Underwater Swimming” image under Public Domain license. It means that you can use and modify it for your personal and commercial projects. If you intend to use an image you find here for commercial use, please be aware that some photos do require a model or a property release. Pictures featuring products should be used with care.