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! Q6 g, N4 ~5 R; j' c公仔箱論壇One of Martyn's diving companions, Robbie Schmittner, in a huge flooded cave in Mexico.
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![](http://i.dailymail.co.uk/i/pix/2010/08/10/article-1301823-0ABF6BF1000005DC-378_964x613.jpg)
9 g4 E( B/ n7 s. R6 Stvb now,tvbnow,bttvbDivers carry remote underwater flash guns to illuminate this image, taken in what is probably the world's biggest underwater tunnel, Weebubbie Cave beneath the remote Nullarbor Plain of western Australia.# ?) Z$ P+ b- y s0 h) |
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9 \' x! O$ p+ S. x* |2 MDivers often use guide-lines to keep them on track in the murky depths. Getting lost can be fatal.0 z8 P! _: i- v [/ l# w, ~3 _ ~
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Deep and dark doesn't always mean cold: Jenny Pinder swims through the underwater passages of the Grotta Giusti Cave in Tuscany, Italy. where geothermal activity heats the water to an amazing 35 degrees centigrade
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In another of Martyn's photos Helen Rider swims through the narrow confines of Taina Cave near Santo Domingo in the Dominican Republic. |