Place
- Loughmoney, Down1
- Lueneburg, Lower Saxony1
- Madron, Cornwall1
- Maen Callwg, Glamorganshire1
- Maenclochog, Pembrokeshire1
- Maes-y-garnedd, Garmon, Denbighshire1
- Magee Island, Antrim1
- Merivale, Devon1
- Midmar, Aberdeenshire1
- Minster in Thanet, Kent1
- Monasterboice, Louth1
- Monmouthshire, England1
- Morbihan, Brittany1
- Morvah, Cornwall1
- Nevern, Pembrokeshire1
- New Grange, counties Meath and Louth1
- Newport, Monmouthshire1
- Newton-Ards, Down1
- North Uist, the Hebrides1
- Northumberland, England1