The road measures 265.49 miles long and would take a car obeying speed limits 6 hours and 46 minutes to travel its length.
The A40 is a A Road and is located in the Zone 4 Highways Region.
This is a true long-distance route, journeying through numerous towns like GOODWICK, FISHGUARD, Dwrbach, Letterston, Wolfscastle, Treffgarne, Rudbaxton, HAVERFORDWEST, Tangiers, Slebech, Canaston Bridge, Robeston Wathen, Sodston, NARBERTH, Llanddewi Velfrey, WHITLAND, St. Clears, Bancyfelin, CARMARTHEN, St. Peters, Johnstown, Pensarn, Abergwili, Whitemill, Nantgaredig, Pontargothi, Dryslwyn, Broad Oak, LLANDEILO, Rhosmaen, Cwmifor, Manordeilo, LLANGADOG, LLANWRDA, LLANDOVERY, Halfway, Llywel, Trecastle, Sennybridge, Trallong, Nantygwreiddyn, Cwmcamlais, Abercamlais, Penpont, Llanspyddid, BRECON, Llanfaes, Llanhamlach, Scethrog, Llansantffraed, Bwlch, Cathedine, Cwmdu, Tretower, CRICKHOWELL, Cwrt Y Gollen, Glangrwyney, Llanwenarth, ABERGAVENNY, Hardwick, Penpergwm, The Bryn, Llanvihangel Gobion, Llanarth, Clytha, Raglan, Dingestow, Mitchel Troy, MONMOUTH, Dixton, Ganarew, Whitchurch, Goodrich, Pencraig, Glewstone, Weir End, Bridstow, Wilton, ROSS-ON-WYE, Greytree, Ashburton Industrial Estate, Hildersley, Weston Under Penyard, Ryeford, Pontshill, Lea, LONGHOPE, May Hill, Huntley, Birdwood, Churcham, Highnam, Over, Walham, GLOUCESTER, Longford, Longlevens, Churchdown, CHELTENHAM, The Reddings, Charlton Kings, Whittington, Andoversford, Shipton Oliffe, Compton Abdale, Northleach, Farmington, Sherborne, Windrush, Little Barrington, BURFORD, Asthall, Minster Lovell, Curbridge, WITNEY, Richmond Village, Barnard Gate, Eynsham, Cassington, Wolvercote, OXFORD, Marston, Old Marston, Headington, Forest Hill, Wheatley, Holton, Barnwood, Milton Common, Tiddington, Tetsworth, Postcombe, Lewknor, Aston Rowant, Stokenchurch, Studley Green, Beacons Bottom, Piddington, West Wycombe, HIGH WYCOMBE, Loudwater, Wooburn Moor, Wooburn Green, BEACONSFIELD, Wilton Park, Jordans, GERRARDS CROSS, Denham, Uxbridge, Ickenham, Hillingdon, Ruislip, Northolt, Greenford, Perivale, Ealing, Acton, Shepherds Bush, East Acton, North Kensington, Notting Hill, Paddington, Maida Hill, Mayfair, Marylebone, Soho, Fitzrovia, St Giles, Holborne, The City, Barbican, and Farringdon.
This is a true long-distance route that passes through multiple counties, including Dyfed, Powys, Gwent, Herefordshire, Gloucestershire, Oxfordshire, Buckinghamshire, Greater London, and City and County of the City of London.