In 2003, Israel began constructing a barrier between Israeli-populated areas in the West Bank and predominantly Palestinian areas. In urban areas, the barrier consists of a 26 foot-high concrete wall punctuated by guard towers. Across the countryside, it consists of a high-tech fence system equipped with motion sensors. The barrier does not follow the pre-1967 borders of Israel, but is instead built around the perimeter of the major West Bank settlement blocs. By some estimates 85 percent is built on formerly Palestinian land. Many Israelis call it “The Security Fence,” arguing that its construction put an end to the wave of suicide bombings that were a major security concern during the Second Intifada. Some Palestinians call it the “Apartheid Wall,” noting that it keeps Palestinians effectively confined and isolated from Israelis as well as separating many villages from their traditional farmland. Palestinians also note the difficulties it creates for workers employed in Israel who have to pass through checkpoints every morning and evening, a process which can take hours.