Over a distance of eight kilometres (five miles), the line climbs around a hundred metres (280 feet) to reach Maron, meaning a gradient of 1:75 and a severe test for engines on the North Western Railway.
Bankers are often required to help trains up the hill. However, they run the risk of being chased by a runaway train - something Duck found out the hard way.
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 James once discovered.
- Gordon's Hill is based on "Lickey Incline" near King's Norton station on the Great Western Railway.
- Whilst it is probably a coincidence, there is a real place in London called "Gordon Hill".
- Between the eighth season and the twelfth season, the curve at the bottom of the hill was not present. The bridge had also disappeared.
- In the ninth season episode, Thomas and the Golden Eagle, there was a road leading to the top of the hill.
- In the fifteenth season episode, Big Belle, the hill was much steeper than usual.
- Since King of the Railway, there is a junction on the other side that goes to Ulfstead Castle.