The Central America-4 Free Mobility Agreement (CA-4; ) is a treaty signed in June 2006 between the Central American nations of El Salvador, Guatemala, Honduras, and Nicaragua, establishing the free movement across borders between the four signatory states of their citizens without any restrictions or checks. Foreign nationals who enter one of the signatory countries can also travel to other signatory states by land (but not by air) without having to obtain additional permits or to undergo checks at border checkpoints. Similar to the Schengen Agreement in Europe, the CA-4 Agreement establishes a harmonized visa regime for nationals travelling to the area. See also Central America-4 passport Visa policy of El Salvador Visa policy of Guatemala Visa policy of Honduras Visa policy of Nicaragua References 2006 in El Salvador 2006 in Guatemala 2006 in Honduras 2006 in Nicaragua Boundary treaties El Salvador–Guatemala border El Salvador–Honduras border Guatemala–Honduras border Honduras–Nicaragua border Honduras–Nicaragua relations Treaties concluded in 2006 Treaties of El Salvador Treaties of Guatemala Treaties of Honduras Treaties of Nicaragua International organizations based in the Americas