A pin tentering apparatus as web transport apparatus includes a tentering mechanism for transporting self-supporting cast film by retaining web edge portions of the cast film. A gas flow device blows evaporative gas to the cast film being transported, to float the cast film. A static pressure adjuster lowers static pressure of the evaporative gas to a web middle portion with respect to a web width direction of the cast film, to regularize distribution of the static pressure in the web width direction. In the gas flow device, a blower duct introduces the evaporative gas. A nozzle plate is positioned at a front end of the duct, and has nozzles which blow the evaporative gas. Preferably, the static pressure adjuster includes an exhaust device, disposed to face the web middle portion between the plural nozzles, for exhausting the evaporative gas.