The Hamelin Pool Marine Nature Reserve is a protected marine nature reserve located in the UNESCO World Heritagelisted Shark Bay in the Gascoyne region of Western Australia. The nature reserve boasts the most diverse and abundant examples of living marine stromatolites in the world, monuments to life on Earth over million years BP. Location and access Hamelin Pool is the eastern major waters within Shark Bay, separated from the western area by the Peron Peninsula, with a smaller water body just adjacent to its northern border with Faure Island - L'Haridon Bight the juncture being defined by Petit Point. At the northern edge of the Hamelin Pool area is the Wooramel Seagrass Bank. The marine reserve is situated adjacent to the Hamelin Station Reserve and the historic Hamelin Pool Telegraph Station about west of the Overlander Roadhouse on the North West Coastal Highway. Access is via Hamelin Pool Road and then through the Hamelin Pool Telegraph Station grounds. Access is free. Marine reserve The Marine Reserve covers . It is one of only a few places in the world where living marine stromatolites can be found. Other locations for stromatolites include an underwater site ( deep) in the Caribbean, Persian Gulf, and in the Great Salt Lake of Utah. Hamelin Pool contains the most diverse range of stromatolites and microbial diversity in the world. The stromatolites in Hamelin Pool were discovered by surveyors working for an oil exploration company in 1956 and were the first living examples of structures built by cyanobacteria. The cyanobacteria living in Hamelin Pool are direct descendants of the oldest form of photosynthetic life on earth. The stromatolites are similar to 3,500 million year old stromatolite fossils found in many places around the world. Stromatolites are an example of the earliest record of life on earth. They are found around the shores, mostly in the neighbourhood of . Hamelin Pool is hypersaline (it has approximately double the salinity of normal seawater), providing an ideal environment for the stromatolites to grow, and inhibiting other marine life which would normally feed on the bacteria. The cyanobacteria live in communities on the sea bed at densities of 3 billion individuals per square metre. They are the simplest life forms to use photosynthesis to provide food and oxygen. They provided the early Earth with most of its oxygen atmosphere billions of years before plants appeared. Very fine particles of solids