The Experimental Engines Yard is a location on the Mainland.
Thomas once stumbled across this yard while on his way to deliver a goods train to Bridlington Goods Yard. He met the locals and filled up again with their coal and water before heading onwards to the Steelworks. He returned to the yard later after escaping Frankie and Hurricane and then enlisted the engines' help to rescue James from their captivity.
It is unknown who owns the yard or where on the Mainland it is located.