In the ancient and beautiful North West Wales town of Harlech, sited on the Wales Coast Path and famed in legend and song, is a street named Ffordd Pen Llech. Residents and visitors who drive down it or walk up it all comment on how steep it is.
“The steepest street (road) is Ffordd Pen Llech in Harlech, Wales, UK with a gradient of 1:2.67 (37.45% stretch over fall) as verified on 6 June 2019”