The following towns currently have Walkers are Welcome status:

Hebden Bridge
Moffat
Dumfries and Galloway
Prestatyn & Meliden North Wales coast
Mytholmroyd
West Yorkshire
Church Stretton Shropshire
Market Weighton,
E Yorks
Kilsyth
Lanarkshire
Pentrefoelas
Bishop's Castle, Shropshire
Richmond,
North Yorks
Otley, West Yorkshire
Cilgerran,
Pembrokeshire
Martley, Worcs
Tadcaster
Rhuddlan
Haltwhistle
Llanfairfechan
Penmaenmawr
Kirkby Stephen
Holywell
Deal
Malvern
Kingsbridge
Llangollen
Leyburn
Pickering
Llandrindod Wells
Winchcombe, Glos
Ross-on-Wye
Ilkley
Llandysul & Pont Tyweli
Wiveliscombe
Newton Stewart
Huntly
Pateley Bridge
Corby
Tomintoul
Chesham
Marsden
Bradfield
Cleobury Mortimer
Dunster
Hayle, Cornwall
Kirkintilloch
Longborough, Glos
Wellington, Shrops
Knaresborough Melrose
Kings Stanley & Leonard Stanley Dufftown
Guisborough
Tregaron

LINKS

Some links which may be of interest to you:

Ramblers Association

Natural England

Countryside Council for Wales

Scottish Natural Heritage

National Trust

National Trust for Scotland

Campaign to Protect Rural England

Open Spaces Society

Campaign for National Parks

Long Distance Walkers Association

National Trails website

Car-free walks