Wonderful World Beneath the Surface: The Great Barrier Reef Experience

Below the bright blue sea off Australia's north coast sits the Great Barrier Reef, the biggest living reef system on Earth. It runs for 2,300 kilometres and holds 2,900 separate reefs - anyone who enters the water meets a busy world of colour plus fish.

When you drop below the surface, you step into a garden of hard and soft corals, odd shaped fish but also animals that look invented for a story. You swim next to green turtles, small reef sharks, rare octopuses and tiny sea peas. The shapes as well as colours hold the eyes of divers and snorkelers - people who love nature put the reef high on their travel list.

The reef stays full of life because the water stays warm or the coast curves in a way that shelters many bays. Corals grow like pink, purple and orange trees - fish flash blue, yellow also silver. Some creatures look like tiny boats that drift instead of swim - yet all fit together inside the coral branches.

Yet the same reef now faces clear danger. Warmer seawater and extra carbon dioxide turn corals white - plastic next to farm runoff smother them. Boats that drop anchors where they should not and fishers who take too much reduce the number of animals. Park zones, clean up crews plus signs that teach visitors how to behave give the reef a better chance to survive for our children.

A trip to the reef gives more than pretty views. You ride boats with glass floors, follow a guide with a snorkel or slip into the water at night to watch plankton light up. Book early, ask local crews where to go and follow their rules so the coral stays unharmed. Once you see the colours for yourself, you understand why people fight to keep the reef alive.