Western Europe [ 1 ] Area 84,421 km 2 (32,595.1 sq mi) [ 2 ] Area rank 20th Coastline 2,797 km (1,738 mi) Highest elevation 1,041 m (3,415 ft) Highest point Carrauntoohil Country   Republic of Ireland Largest city Dublin   United Kingdom Constituent Country Northern Ireland Largest city Belfast Demographics Population 6,399,152 [ 3 ] (as of 2011) Density 73.4 /km 2