JERUSALEM - Israel's West Bank separation barrier, where Pope Francis made an unscheduled stop Sunday, is a vast structure that places a major physical obstacle between Israel and the occupied Palestinian territories.
Israel refers to it as the "security fence" with the government insisting it is crucial for keeping out would-be attackers and pointing to the welcome absence of suicide bombings and other bloody attacks since construction began.
But the Palestinians have branded it the "Apartheid wall," and say it is a thinly disguised land grab aimed at stealing part of their future state.
Israel began building the barrier in 2002 at the height of the second Palestinian intifada, or uprising, with UN figures showing that more than two-thirds of it has been completed.
A network of towering concrete walls topped by Israeli guard towers, tangled barbed-wire fences, trenches and closed military roads, the barrier will extend some 712km when completed - most of it inside the West Bank.
Only 15 per cent of its route follows the Green Line, which is recognised by the international community as Israel's border.
The rest is inside the West Bank, cutting off thousands of Palestinians from their land.
In 2004, the International Court of Justice issued a non-binding resolution calling for those parts of the barrier inside the West Bank to be torn down and for further construction in the territory to cease.
Israel has not complied with the ICJ ruling, and has resisted calls to route the barrier along the Green Line, the 1949 Armistice Line established after the end of fighting that accompanied Israel's establishment a year earlier.
In places where the barrier is a concrete wall, it has become a blank canvas on which hundreds of people vent their frustration and anger, covering it with multi-lingual graffiti and slogans.
Parts of it are covered with huge murals and artwork, including some by British graffiti artist Banksy. In other places, local restaurants have used the wall to screen events such as World Cup football matches.
Two days before the pope's arrival, workers employed by the Israeli army could be seen painting over graffiti on the section of the wall in Bethlehem where Francis' convoy was to pass.
But by Sunday morning, the newly painted section was covered with a fresh batch of slogans, and the pope stopped there to pray.