Pack of mushrooms growing in wood-chippings. Up to 100mm across.
Caution: Do NOT use iSpot to identify fungi to eat!
Some fungi are very poisonous so a mistaken ID could have serious consequences.
No interactions present.
These photos aren't too helpful, but I'd imagine this is Volvariella gloiocephalla. The gills look dark, bit I'd bet the spores were pink.
Lat/Lng: 53.7079, -1.8912
OS grid ref: SE072235
By side of track