The nation's borders were the prime location for much of HMCE's work. Before the 20th century the UK's only border was its coastline and customs activity was focused around the coast. The establishment of the Irish Free State in 1922 gave the United Kingdom a land border, which also required customs checkpoints; later, customs officers were needed at airports as well. As well as administering Customs declarations, HM Customs and Excise staff had responsibility for guarding the borders of the United Kingdom from smugglers. To try to achieve this, HMCE and its predecessors had a history of operating both on land and at sea.