The gift store is the main entrance and the top of the stairs are inside the store. You enter the store, pay & sign the waiver then walk down the stairs to the cave.
The entrance to the store is Street level and essentially the top floor. When I went, as I approached the store, an employee asked me if I was just going for the shop, or if I was going to go down the stairs into the cave? I said the cave, so she had me get in line with a couple of other folks that were already there. Only waited a few minutes before she let us in to the store to pay our entrance to go down into the cave. If you're not going to go down into the cave, they will let you right in to the store to shop.
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