Toyooka lies entirely within the San’in Kaigan Geopark. One of Toyooka’s famous geological features is a basalt cave called Genbudo. Genbudo was formed 1.6 million years ago from the eruption of an ancient volcano. In 1926, Professor Motonori Matuyama of Kyoto University first proposed the theory of geomagnetic polarity reversal at Genbudo after discovering it had a reverse magnetization.
The wetlands of Toyooka provide an important habitat for the oriental stork. After becoming extinct in the wild in the 1970s, Toyooka began a captive breeding program. After a quarter of a century of breeding efforts, the first oriental stork chick was born in 1989. In 2005 Toyooka released 5 captively bred storks, which bred successfully in the wild. As of June 2015 there are 72 wild oriental white storks in Toyooka.