And when this happens under the nose of millions of tourists at the most trodden-through set of caves in Australia, the Jenolan Caves, it is even more exciting.
Hundreds of metres of spectacular caves have been found by an intrepid team from the Sydney University Speleological Society, the first significant find at the cave system for almost 40 years.
They are hard to reach, but worth the uncomfortable journey. Purple-tinged flowstones and rare red-coloured stalactites and stalagmites paint a vivid underground portrait.
The floors are covered with light-reflecting crystals. Unusually patterned bands of gravity-defying helictites line the walls.
Intricate multi-tiered domes and crystallised streams also form part of the newly discovered network, which is too difficult to access to form part of a future tourist track.
Millions of tourists and thousands of explorers have picked over the cave system since it was discovered in the 1830s, when they were used as a hideout by an escaped convict.
One of the world's leading experts on limestone caves, Armstrong Osborne of Sydney University, said the find filled in significant gaps in the knowledge of the cave system, which was in July named the world's oldest at 340 million years.
"Jenolan is one of the world's most complicated cave systems," he said.
"These passages form an important connection between the parts that are used as the show caves, and other parts which are only seen by explorers and specialised caving clubs.
"What is significant is that it is extremely well decorated, with some very fragile mineral deposits and formations. There's some remarkable crystal pools - the floor is covered with calcite crystals which make the floors sparkle. It is very fragile. You cannot walk on it."
Felisse Fraser, who visited the caves for the first time in July, said she was awe-struck by the beauty of the chambers. "It was unbelieveable. There was a real sense that you were standing in a sacred spot, witnessing history," Ms Fraser said. And although she dared not touch any of the crystals, she said she couldn't help admiring the sparkling features growing from the cave's roof, floor and walls. "Every woman loves a bit of bling-bling, and it's everywhere. It's gorgeous."
Speleological Society president Keir Vaughan-Taylor said the find was an "archetypal discovery". "They pulled a piece of rock out and there was this passageway," he said. "We still don't know where the passageways will lead. There is still much more to find.
"These caves take you aback with how spectacular they are. It goes to show that not all has been found in this world, not by a long way."
Jenolan Caves Trust spokesman Grant Commins said caving experts were astounded by the find. "The experts all comment on the astonishing beauty of the caves," he said.
Alan Pryke, a photographer with The Weekend Australian's and a member of the Speleological Society, said most of the newly discovered passages were extremely tight and the new chambers tortuous to access.
"It is basically an assault course to get to the highly decorated area," he said. "They are very unlikely to ever be tourist caves."
Source: The Australian