Earlier this month, Agence France-Presse photographers Jim Watson and Guillermo Arias traveled the length of the U.S. / Mexico border, one on each side, documenting the landscape and people along the way. Watson on the U.S. side, and Arias on the Mexican side, spent ten days traveling the 3,169 kilometers (1,969 miles) from California / Baja California to Texas / Tamaulipas.