All the London railway stations :
Chesham is on the Metropolitan Underground, and is deemed to be accessible to wheelchair travellers, although be aware of the large step onto trains. The newer metropolitan trains do not suffer this problem. See pictures and further accessible transport in London detail from links below.
Underground lines : Metropolitan
AccessAble Access Guide : Metropolitan
Accessibility friendly : Partial. (A step 160mm/gap 33mm)
There is level access between the street and platform 3.
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