The top-level division of administrative geography in the UK is the 4 countries – England, Scotland, Wales and Northern Ireland.
As well as the national government at Westminster, there are also devolved administrations in Edinburgh, Cardiff and Belfast.
The UK and its countries: facts and figures
| UK | England | Scotland | Wales | Northern Ireland | |
| Area (km2) | 248,531.52 | 132,937.69 | 80,239.47 | 21,224.63 | 14,129.72 |
| Population* (millions) | 63.7 | 53.5 | 5.3** | 3.1 | 1.8** |
| Pop. density* (per km2) | 263 | 411 | 68** | 148 | 135** |
| Highest Mountain | Ben Nevis
(1,344 metres) |
Scafell Pike
(978 metres) |
Ben Nevis
(1,344 metres) |
Snowdon
(1,085 metres) |
Slieve Donard
(852 metres) |
| Longest River | Severn***
(354km) |
Thames
(346km) |
Tay/Tummel
(188km) |
Towy
(121km) |
Bann
(122km) |
| Largest Lake | Lough Neagh
(392km2) |
Windermere
(14.7km2) |
Loch Lomond
(71km2) |
Lake Vyrnwy
(4.5km2) |
Lough Neagh
(392km2) |
* Mid-2012 population estimates.
** Please note that the Scotland population figures are sourced from National Records of Scotland (NRS) and the Northern Ireland population figures are sourced from the Northern Ireland Statistics and Research Agency (NISRA).
*** The Severn rises in Wales and flows through England to its estuary in the Bristol Channel.
The Thames and the Towy are the longest rivers entirely in England and Wales respectively.
