Wales
Wales packs an unusual amount of variety into a small country: a mountainous north, a long western coastline, and a gentler, more agricultural south and east.
The old counties still do most of the work for self-catering purposes: Anglesey and Conwy for the north coast and its beaches, Gwynedd for Snowdonia and the Llŷn Peninsula, Denbighshire for the Vale of Clwyd, and Cardiganshire, Carmarthenshire and Pembrokeshire running down the west coast — Pembrokeshire in particular is known for its coastal path and some of the best beaches in the country. Further east and south, Monmouthshire, Powys and the Wrexham area give a quieter, more rural alternative, closer to the English border, while South Wales covers the Gower coast and the valleys.
North or south
North Wales suits anyone wanting mountains and a dramatic coastline within a short drive of each other — Snowdonia and Anglesey's beaches are barely an hour apart. West Wales, particularly Pembrokeshire and Cardiganshire, is the better pick for a coastal-path walking holiday or a beach-focused family week. The Marches and Powys, being that bit closer to the Midlands and the south of England, are worth considering if travel time matters and you still want a genuinely rural, hilly setting.