Photo at Ringby Lane, Ploughcroft, Halifax, today.
Foodplant for the larva is usually Cocksfoot grass. A common and easily-identified grass once you get your eye in for it. Apart from good for butterflies, summer is the best time to learn and appreciate the many kinds of grasses that flower in Calderdale. 
I should point out that despite being the “Large” Skipper it is only 12 -18 mm long on it’s fore-wing. (M.Chinery)
The other two Skippers we get in Calderdale  – Small Skipper and Dingy Skipper (infequent) are very slightly smaller. The Large and the Small are quite common where sun-drenched long grass is allowed to exist.