Over a distance of eight kilometres (five miles), the line climbs around a hundred metres (280 feet) from Suddery Junction to reach Dragonland, meaning a gradient of 1:75 and a severe test for engines on the Southern Railway.
Bankers are often required to help trains up the hill. However, they run the risk of being chased by a runaway train or rear ending the train they are helping - something Brody Duck found out the hard way twice, once with Matol and again with Yogi.
When the railway was first built, this stretch was made even more difficult by strong winds blown in by the sea. This was attempted to be countered by the planting of trees on either side of the line, but in autumn there can be the additional risk of slippery leaves on the line, as Diesel soon discovered. [[ Thomas & Friends]]
Obelix's Hill has been seen frequently throughout the television series. Edward is usually seen banking engines on the hill, though ocasionally other engines such as Toby and Riki have done the job.
In the sixth series, Mr. Jolly's Chocolate Factory was located at the bottom of the hill, however since when a calliope ran away from Geki and came off the rails at the bottom of the hill, or when a giant snowball knocked Emily off of the tracks.