The Hawin Croka is a large river which starts several hundred metres west of the Hawin Russagh in the south of Ward Fell. It then winds past Kellsthorpe and Rolf's Castle before reaching the bay near Kirk Ronan. The North Western Railway crosses the stream twice. The Main Line crosses it west of Kellsthorpe Road, and the Kirk Ronan Branch Line crosses it at Rolf's Castle.
The river was first seen during the third season as a canal that runs along the railway, the canal also appeared in stock footage in the seventh season, the river was also seen in the 2000 film, Thomas and the Magic Railroad as the Big Dipper crosses over the river.