 The Frome Valley Walkway is a public footpath , 18 miles ( 29 km ) long , that runs almost the entire length of the river from Old Sodbury to Bristol . A guide pamphlet has been published . The walkway was created by a partnership between local authorities , the Environment Agency , wildlife organisations and location action groups , including Avon Biodiversity Partnership , Avon Invasive Weeds Forum , Avon Wildlife Trust , Bristol City Council , Bristol Naturalists ' Society and South Gloucestershire Council . Regular events include clearing of invasive species and guided walks . 
