The ESA Open Water Explorer course has been created for those people who are in good physical health and want to learn to snorkel, taking advantage of all the benefits that this course has got to offer. The ESA Open Water Explorer course introduces the snorkelling activity, within the limits of the snorkelling certification and under the same conditions encountered during the basic training course. During this course, participants will have the opportunity to learn and apply all the fundamental notions and techniques useful to practice the snorkelling and to explore the aquatic world in more safety way. The participants to this course will receive important information and will learn all about the equipment used for snorkelling. Keeping in mind the targets, this course will try to meet individual needs, taking into account time and learning skills.