Decades ago there was only one certification: Diver. It took us nine weeks to get certified. Some folks balked at the amount of time required, especially if they had a trip coming up. To make more customers, the course was (kind of) split in half and called Open Water I and Open Water II.
If you could dive as an OW I, why take the second course? To make it more attractive, it was renamed "Advanced". I believe a person can become an Advanced Open Water diver with only 10 or 20 dives. Although it probably makes for an improved diver, OW II may be a more appropriate name for it.
If you could dive as an OW I, why take the second course? To make it more attractive, it was renamed "Advanced". I believe a person can become an Advanced Open Water diver with only 10 or 20 dives. Although it probably makes for an improved diver, OW II may be a more appropriate name for it.