<P> The Caribbean trade bloc--CARICOM--came into agreement in 1973 when it was signed by 15 Caribbean nations . As of 2000, CARICOM trade volume was US $96 billion . CARICOM also allowed for the creation of a common passport for associated nations . In the past decade the trade bloc focused largely on Free Trade Agreements and under the CARICOM Office of Trade Negotiations (OTN) free trade agreements have been signed into effect . </P> <P> Integration of Central American economies occurred under the signing of the Central American Common Market agreement in 1961; this was the first attempt to engage the nations of this area into stronger financial cooperation . Recent implementation of the Central American Free Trade Agreement (CAFTA) has left the future of the CACM unclear . The Central American Free Trade Agreement was signed by five Central American countries, the Dominican Republic, and the United States . The focal point of CAFTA is to create a free trade area similar to that of NAFTA . In addition to the United States, Canada also has relations in Central American trade blocs . Currently under proposal, the Canada--Central American Free Trade Agreement (CA4) would operate much the same as CAFTA with the United States does . </P> <P> These nations also take part in inter-continental trade blocs . Mexico takes a part in the G3 Free Trade Agreement with Colombia and Venezuela and has a trade agreement with the EU . The United States has proposed and maintained trade agreements under the Transatlantic Free Trade Area between itself and the European Union; the US - Middle East Free Trade Area between numerous Middle Eastern nations and itself; and the Trans - Pacific Strategic Economic Partnership between Southeast Asian nations, Australia, and New Zealand . </P> <P> The Pan-American Highway route in the Americas is the portion of a network of roads nearly 48,000 km (30,000 mi) in length which travels through the mainland nations . No definitive length of the Pan-American Highway exists because the US and Canadian governments have never officially defined any specific routes as being part of the Pan-American Highway, and Mexico officially has many branches connecting to the US border . However, the total length of the portion from Mexico to the northern extremity of the highway is roughly 26,000 km (16,000 mi). </P>

What is common about the location of urban areas in united states/canada