The town is the site of one of the world's great fossil discoveries. A road worker in 1956 found 360 million year old fish fossils. These were from the Devonian period in the Palaeozoic era. The "Canowindra slab" was taken to the Australian Museum, Sydney. The fish had been trapped in a pool of water that dried up. The fish found were two armoured antiarch placoderms, "Remigolepis walkeri" and "Bothriolepis yeungae." They also found "Canowindra grassi", a lobe-finned crossopterygian fish, with two rare young arthrodire placoderms, "Groenlandaspis" species.