The North Sulphur River was channelised a century ago, and the river has been cutting down into Cretaceous chalk ever since, exposing a continuous fossil bed. Ladonia Fossil Park gives free public access to it. Ammonites, shark teeth, mosasaur and plesiosaur material all come out. Walk the riverbed, not the banks, go in dry weather, and be aware it floods fast.
Ammonites, shark teeth, mosasaur · Late Cretaceous, ~80 mya
See it on the map
Other places on the map within a couple of hours.
