C.P. Huntington. It's simply the best ridable miniature train out there, and I am proud to be an operator of these trains at my local zoo. EDIT: Irvine Park has since acquired a new electric train and the old train has been auctioned off.
Those are diesel engines. Just like the trains at the St. Louis Zoo. Those engines were donated by GM, Chrysler, or some major vehicle manufacture. If you listen carefully, you could here the low rumble of diesel engine.