At least 45,000 Cubans are expected to travel by bus, boat, taxi and on foot from Ecuador and other South and Central American countries to the US this year, afraid that the normalisation of relations between the US and Cuba will mean an imminent end to special immigration privileges that date from the Cold War.

Cuban migrants
Cuban migrant Rudy Correa hugs his daughters after they arrived in La Miel in the Panamanian province of Guna Yala, having crossed the border from Colombia through the jungleCarlos Jasso/Reuters

While migrants from across Latin America struggle to get green cards and many live illegally in the US, fearful of deportation, Cubans receive residency with ease under the US Cuban Adjustment Act of 1996.

The overland exodus has caused a border crisis in Central America, set off tensions in the newly friendly US-Cuban relationship and sparked rising calls in the US to end Cubans' automatic right to legal residency once they touch American soil.

Cubans start with an advantage other migrants can only dream of: many countries along the route grant Cubans free passage because their government does not respond to most requests for information about illegal migrants that would allow them to be deported. Many Cubans who run out of money along the way have access to hundreds or thousands of dollars in backup funds sent by relatives who belong to one of the US' most prosperous immigrant groups.

Once they reach the US border, they can just show up at an established port of entry and declare their nationality, avoiding the dangerous desert crossings that confront many migrants who try to avoid US Border Patrol. Federal data shows 45,000 Cubans appeared at US land border points in the 12 months ending 20 September 2015, and at least as many are expected in the coming year.

But along the way, Cubans still must navigate jungles, rivers, at least seven international borders and countries in the grip of gangs responsible for some of the world's highest homicide rates.

Cuban migrants
Cuban migrants camp during sunset in La Miel, in the province of Guna Yala, PanamaCarlos Jasso/Reuters
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Cuban migrants celebrate in the water upon arriving in Panama after crossing the border from Colombia through the jungleCarlos Jasso/Reuters
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A woman dries packs of Cuban cigarettes after she crossed the border from Colombia through the jungle into La Miel, in the province of Guna Yala, PanamaCarlos Jasso/Reuters
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A Cuban migrant smiles as she climbs down a slope after she crossed the border from Colombia through the jungle into La Miel, in the province of Guna Yala, PanamaCarlos Jasso/Reuters
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A Cuban migrant, with a tattoo of Che Guevara, is seen after arriving safely in La Miel in the province of Guna Yala in Panama, having crossed the border from Colombia through the jungleCarlos Jasso/Reuters
Cuban migrants
Cuban migrants walk as they arrive after crossing the border from Colombia through the jungle into La Miel, in the province of Guna Yala, PanamaCarlos Jasso/Reuters
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Cubans' passports are seen on a desk at the Border Police office in La Miel, in the province of Guna Yala, PanamaCarlos Jasso/Reuters
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Cuban migrants brace themselves against the spray as they continue their journey to the north by boat to Puerto Obaldia in the province of Guna Yala, PanamaCarlos Jasso/Reuters
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Cuban migrant Yamilen Arbelo, 40, hugs her son and a friend after she crossed the border from Colombia through the jungle into La Miel, in the province of Guna Yala, PanamaCarlos Jasso/Reuters
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Marisol Rosales, 63, slides down a hill after she and fellow Cuban migrants crossed the border from Colombia into Panama through the jungleCarlos Jasso/Reuters
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The feet of a Cuban migrant are pictured after she arrived safely in La Miel in the province of Guna Yala after crossing the border from Colombia through the jungleCarlos Jasso/Reuters
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Cuban migrants sleep by the doorway of a house as they wait for their flight or boat tickets, in Puerto Obaldia in the province of Guna Yala, PanamaCarlos Jasso/Reuters
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Alfredo Daniel Rosas and his wife Aylen Anzardo, who is six months pregnant, pose for a photograph at a shelter in La Cruz, Costa RicaJuan Carlos Ulate/Reuters
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Cuban migrant Odlanier Gil and his girlfriend Angely Dominguez embrace as the sun sets in the town of La Cruz, Costa RicaJuan Carlos Ulate/Reuters
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Cuban migrant Juan Pablo Zavedra plays with Diogo Carmelo at a shelter in La Cruz, Costa RicaJuan Carlos Ulate/Reuters
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Cuban migrant Yusniel Rodriguez and his wife Ariagna Batista, who is five months pregnant, look at their mobile phone at the border between Costa Rica and Nicaragua, in Penas Blancas, Costa RicaJuan Carlos Ulate/Reuters
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Nicaraguan soldiers stand guard at the border between Costa Rica and NicaraguaJuan Carlos Ulate/Reuters
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Cuban migrants wait to board a bus to take them to a shelter, outside the immigration office at the border between Costa Rica and NicaraguaJuan Carlos Ulate/Reuters
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Osmael Blanco holds his two-month-old daughter as her mother, Yuneisey Padron, looks on in Puerto Obaldia in Guna Yala province, PanamaCarlos Jasso/Reuters

When migrants are stopped by border guards along the route, officials' first step is contacting the migrant's country to confirm their identity. In the case of Cubans, that's often impossible. The Cuban government doesn't respond to as many as 90% of inquiries about people with Cuban passports but no visas, said Mario Madrazo Ubach, head of immigration control at Mexico's National Migration Institute. Since entering the country without a visa in itself isn't a crime in Mexico, Mexican authorities generally give the Cubans 20 days to leave the country, which they use to get to the US border and claim legal residency. Similar scenarios take place throughout Central America.

Cuban migrants
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Cuban migrants
A man counts money after charging Cubans $200 each to travel by boat from Puerto Obaldia in eastern Panama to Panama CityCarlos Jasso/Reuters
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Cuban migrants stand in line to receive breakfast at a shelter in La Cruz, Costa RicaJuan Carlos Ulate/Reuters
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Cubans celebrate near the Ecuadorean embassy in Havana after Ecuador said visas will be issued to Cubans who had bought airline tickets to the country before 26 NovemberYamil Lage/AFP
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A man wearing a T-shirt bearing the US flag rests in a shelter in La Cruz, near the Costa Rica-Nicaragua borderEzequiel Becerra/AFP
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A Cuban man in a group of 150 resting in a shelter in the Costa Rican town of La Cru near the border with Nicaragua holds a US flagEzequiel Becerra/AFP
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Osmel Garcia shows a Costa Rican visa in his Cuban passport in a shelter in the town of La Cruz , Guanacaste, Costa RicaEzequiel Becerra/AFP

However, countries along the well-trodden route have begun clamping down on the flow of Cuban migrants. Some 1,200 Cubans had been stuck in Panama, attempting to cross into Costa Rica when Costa Rica suddenly tightened its immigration policy, then reversed course and allowed the Cubans in. However, after passing through Costa Rica they were stopped at the Nicaraguan border. Ecuador has now announced it would require visas from Cubans starting 1 December.