The Pregnant Lady
A few of us made our way through another branch of the Blue Lagoon cave known as The Pregnant Lady because the entrance is so tight that no one who is pregnant could do it (nor could anyone even a pound more muscular than Curt). Curt got in only by exhaling completely while he squeezed his way through the initial passage, which then opens up as is seen here. At the end, you once again swim under a rock wall and surface back in the main chamber.
From Fiji 2014