No fun? Tourists and their euros steer clear of Greek resorts.

In a crowded alleyway at the foot of the Acropolis, the Adrianos travel agency is uncharacteristically empty.

Manos Georgakarakos has owned the business for 42 years. This is the worst year he can remember.  

“Normally at this time of the year we are packed, we have tourists queuing out the door. But I would say tourist numbers are now 50 percent down. Last minute bookings are 30 percent down,” he says.

The timing couldn't be much worse. Greece is locked in desperate negotiations with its international creditors – the International Monetary Fund, the European Central Bank, and the countries of the eurozone. Unless a last-minute deal to provide urgently needed money can be hammered out at an emergency meeting of all 28 European Union leaders in Brussels on Sunday, the country is likely to go bankrupt and crash out of the eurozone.

And the ripples from those negotiations, combined with a six-year recession made worse by austerity, are hobbling Greece's critical tourism industry just as the income it generates is most needed by Greeks.

“This will finish Greece," says Mr. Georgakarakos. "We have only tourism – nothing else. And it’s happening in July, right in the middle of the season.”

Spooked tourists

Tourism is the life blood of the Greek economy. If it dries up, the already grim economic crisis will worsen. More than 17 percent of Greece’s GDP depends on tourism, according to the World Travel and Tourism Council, with around 350,000 Greeks directly employed in the sector.

There has been a sharp reduction in bookings since Sunday, when Greece held a referendum on whether to swallow more austerity in return for another bail-out.

The "No" vote – rejecting any such deal – won an overwhelming victory, with 62 percent of the vote, in what many European leaders regarded as a slap in the face, after five months of painstaking negotiations with the radical leftist government of Alexis Tsipras, the prime minister.

"Since the announcement of the referendum and the imposition of capital controls, we have seen a 30 percent drop in last-minute bookings,” says Xenophon Petropoulos, communications manager for the Association of Greek Tourism Enterprises.

“An immediate and sustainable agreement with our European partners needs to be reached so that the positive image of our country abroad can be restored and the economy – with an emphasis on the Greek tourism sector – returns to normal.”

Tourists have been spooked by dire warnings of shuttered banks, difficulties paying with credit cards and the specter of civil unrest – Athens has been no stranger to riots over the last six years.

Kim Smith, a tourist from Washington, contemplated canceling her trip to Greece, but in the end went ahead, largely because she wanted to visit her sister, who lives in Athens.

“We were concerned deeply. On CNN they’ve been showing Greeks eating out of trash cans and queues outside bank ATMs. All our friends told us not to come, that it was dangerous. I thought many times of canceling the trip but there was a lot of money at stake – we would have lost out had we canceled.”

Emptier islands

She was on a fast hydrofoil from Athens to Hydra, an idyllic island of whitewashed monasteries and pebble beaches off the Peloponnese.

So far the island has only had a few cancellations by foreign tourists, but it is being hit hard by the fact that middle-class Athenians, who once saw it as an easily accessible weekend getaway, are no longer visiting.

The hydrofoil alone costs 50 euros round trip, at a time when Greeks are allowed to withdraw just 60 euros a day in cash from bank ATMs.

The 14-mile-long island is stunning – vivid purple bougainvillea covers white-washed walls, cafes line the quay of the only port, and cars, motorbikes, and even bicycles are banned, with transportation provided by mules and donkeys. But its beauty belies a growing sense of desperation.

An increasing number of islanders are struggling financially and the council is providing free food supplies, including pasta, olive oil, and sugar, to more than 70 families who can no longer afford to put a meal on the table.

“If the situation deteriorates, then we will face a humanitarian crisis,” said George Koukoudakis, a lecturer in international relations who was elected mayor last September. “This really worries me. Outside the tourist season, unemployment is now 70 percent. Our social cohesion is going to be threatened.”