Noun
The layer of gravel or other foundation on which a railway track is laid.
Synonyms: bed, railbed
(loosely) The land on which a railway (especially one that has been closed or dismantled) was built; the roadbed for a railroad.
Holonym: right of way
Most other closed lines within the county were long ago lifted and much of the trackbed has returned to agricultural use. Source: Internet
No one on the train was injured, but 25 passengers waiting on the platform for another TGV were slightly injured by ballast that was thrown up from the trackbed. Source: Internet
The trackbed from Accrington to Baxenden is now a linear treelined cycleway/footpath. Source: Internet