Os Muros (visíveis) que ainda permanecem

WEST BANK Israel says the West Bank barrier is essential to protect itself from attack but to the Palestinians, it is an "apartheid wall". Concrete controversy .  NORTHERN IRELAND Designed as a temporary measure to keep fighting Protestant and Catholic communities apart, many "peace walls" are stills standing. Troubled communities .  CEUTA AND MELILLA Residents of Spain's north African enclaves live behind towering fences, designed to keep out would-be illegal migrants trying to reach Europe. European gateway .  CYPRUS Built after the 1974 war, the no-man's land between Greek and Turkish Cypriots on the island remains under UN control. Divided island .  RIO DE JANEIRO Brazil says the walls are to protect the forest from growing shanty towns, but critics say they are an attempt to hem in the city's poor. 'Poverty barrier' .  US-MEXICO The US spends millions of dollars on a vast fence and surveillance operation along its southern border to try to keep illegal migrants out. Operation Guardian .  KOREAN BORDER The heavily guarded "De-militarized Zone" (DMZ) between North and South Korea remains a symbol of Cold War on the peninsula. Cold War remnant WESTERN SAHARA Morocco's wall of sand in the Sahara desert is an attempt to keep out the Sahrwari people, who also claim the territory as their own. Desert sands SAUDI ARABIA The most powerful economy in the Gulf is  building one of the longest, most high-tech  security fences in the world, at a cost of $300m. High-tech frontier .  PAKISTAN-IRAN Baluchistani communities are divided by Iran's barrier  on its border with Pakistan, intended to keep out  smugglers and migrants. Communities split . INDIA-PAKISTAN The mined and heavily guarded border between India  and Pakistan is one of the most volatile frontier regions on the planet. Volatile frontier . BOTSWANA-ZIMBABWE Botswana's hopes the extensive fence  will protect its valuable livestock from disease,  but Zimbabwe says its real purpose is to keep people out. Disease barrier