From 1948 to 1967, residents of Egyptian Sinai and neighbouring Gaza considered the area as a single territory.
But in the 1967 Arab-Israeli war, Israel captured Sinai and the Gaza Strip.
Twelve years later, Israel and Egypt signed a peace treaty which returned control of Sinai to Egypt; but the Israeli occupation of Gaza continued. In 1982, a wall was built to separate the two territories - a wall which still stands today.
"They started building the wall at midday," says Alaa Attiya Issa, recalling that day in April 1982. "I was at my uncle's house on the Palestinian side of Rafah. At 11:15am my uncle said 'They'll close the border at midday. You'd better go home now so you don't get stuck'. I said goodbye and cried."
"We hadn't expected that to happen," he says. "A wall was built and the Palestinian side of Rafah was separated from the Egyptian side. Those on the Sinai side stayed there, and those on the Palestinian side stayed there. It happened just like that."
Issa, a former footballer, once played for Rafah FC in Sinai. But because of the wall, he decided to move back to Palestine, settle in Gaza and give up football.
From the start, the wall divided families, split communities and carved some towns in two. Routines were disrupted, trading relationships undermined, health and education affected - whole ways of life turned upside-down.
The life of Samya al-Agha, an Egyptian, was affected by the wall soon after her marriage to a Palestinian from Gaza. The border wall went up just 20 days after they were wed, separating her new home from her Sinai family in Arish.
"One half of the family lives in Egyptian Rafah and the other half in Palestine," she says.
"My father used to work in Palestine. He used to move freely between the two countries ... He used to come here to farm. It was all one piece of land. He even used to go to Friday noon prayer in Gaza. He and my grandfather used to ride a camel to the Grand Mosque in Khan Younis. They didn't even realise these were two different countries. They thought it was all one."
Bedouin tribes living between the territories also saw their lives change overnight.
"After the wall was built, our al-Tarabin tribe was divided into two parts," says Najeh al-Hamidi, a Bedouin born in Gaza but now living in Sinai. "People call them Palestine's al-Tarabin and Sinai's al-Tarabin though we're one tribe and one family going back to the same great-grandfather."
"The problem is not the people," he says. "The problem lies with international law. It doesn't take humanity into consideration."
Although the region’s peaceful social coexistence ended in 1982, older residents on both sides of the wall hold on to their memories of life as it was before they were separated.
In spite of the metal and concrete barrier and the harsh political reality it represents, they remain firm in their belief in the unity of the spirit of those on either side.
"I'm now standing here, only 10 metres away from the Sinai side of Rafah but I can't go there," says Issa, looking beyond the wall. "This is not just an occupation. It's a responsibility. We're supposed to be one people and one country."