
+ b) O' ?4 o: b8 K( ~' a( d8 f- |公仔箱論壇One of Martyn's diving companions, Robbie Schmittner, in a huge flooded cave in Mexico.
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Divers 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./ D R, c. g( r1 W6 L& _, \% v
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) X0 p! @* C- z$ h3 eDivers often use guide-lines to keep them on track in the murky depths. Getting lost can be fatal.tvb now,tvbnow,bttvb( B f* _+ @7 s- D- @
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# I, \6 \3 n8 f' |公仔箱論壇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$ G5 I: h, O6 |+ H0 v* j2 p
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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. |