Latvia

Latvia's pair is a capital and the beach it goes to. Riga holds the largest concentration of art nouveau architecture of any city in Europe — roughly a third of the buildings in its centre, most of them put up in a fifteen-year burst before 1914 — and Jūrmala is thirty kilometres of pine and wooden dachas along the gulf. The two have been read as one place by their own residents for a century: the train between them takes half an hour and has done since 1877.