After decades of debate, Panama was chosen as the site for a trans-Central American canal because Nicaragua, the rival site, is volcanically active. The French used this fact to successfully lobby the United States Congress to build a canal in Panama.
The French, who had already built the Suez Canal, were the first nation to seriously investigate a trans-Central American canal. After decades of investment, however, poor engineering decisions and regional conflict had nearly halted any construction. The French proposed selling the partly completed Panama Canal to the United States, but the U.S. Congress wanted a canal in Nicaragua. After a volcano erupted in Martinique, a French lobbyist found Nicaraguan stamps commemorating Nicaragua's Momotombo Volcano. He distributed the stamps among U.S. Congressmen, and votes quickly shifted from Nicaragua to Panama. The purchase was finalized in 1902.