Indiana's state parks
... that Indiana's state parks were initially designed to preserve their natural state, but gradually began to include recreational activities?
... that <b id="mwCYM"><a href="./List_of_Indiana_state_parks" id="mwCYQ" rel="mw:WikiLink" title="List of Indiana state parks">Indiana's state parks</a></b> were initially designed to preserve their natural state, but gradually began to include recreational activities?