Search london history from Roman times to modern day
A bit out of date, but this interactive map of step free London is very good
All the London railway stations :
Underground lines : National Rail South West
AccessAble Access Guide :
Accessibility friendly : Yes.
General description : Hounslow is accessible to wheelchair users with level access to both platforms. Interchange between platforms is via a footbridge with steps or by road immediately outside station. See wiki
More comment : National Rail Map & Guide