The Washington Post has mapped the frequency of visits of U.S. Secretaries of State to foreign nations since 1989.
According to the map, the top visited nations by U.S. Secretaries of State Baker, Christopher, Albright, Powell, Rice, and Clinton include: Israel, with 90 visits, followed by Egypt with 61 visits, Syria with 48 visits, the Palestinian authority with 47 visits, and Jordan with 35. Other nations frequently visited include: Britain, France, Germany, Belgium (NATO headquarters), Spain, Italy, Switzerland, Russia, South Korea, Japan, Turkey, Saudi Arabia, Canada, and Mexico.
For the interactive map, visit: Washington Post: Fascinating interactive map: Where U.S. secretaries of state have traveled since 1989