There was barely room to steer a luggage trolley at Gatwick’s south terminal at points on Thursday. Passengers stood in long queues at check-in desks and information points, trying to establish when – or if – they would be able to travel.

Others, already dispirited by news of long delays, sat slumped on floors and in packed cafes, many with large piles of bags that they had not been able to check in.

The sighting of drones over the runway overnight at the West Sussex airport had ruined plans for thousands of Christmas holidaymakers. The runway was closed after the drones were sighted at 9pm on Wednesday. On Thursday evening, the airport’s chief operating officer, Chris Woodroofe, said it was impossible to tell when flights would resume.

Gatwick airport: easyJet cancels all flights today as it's unclear when runways will reopen – live Read more

Zak Morgan, 20, a computer science student at UCL, had been waiting since 8.45pm on Wednesday for what should have been a 30-minute flight to Paris. He had made it on board, only to sit there for hours, before being told to get off. The journey was rescheduled via Barcelona, to depart at 3pm. But that flight was also cancelled. Asked why he didn’t just go home, he said: “Every hour they have been changing the flight times, so instead of saying go home, they’ve been telling us to stay.”

Arthur Serbejs, 22, and Domante Balciunate, 21, factory workers from Hastings, had been waiting just as long. They were sitting on the floor by a prayer room, approaching their 19th hour of waiting for a flight to Barcelona.

“We came about 6pm yesterday,” Serbejs said. “At 9pm yesterday we were on the plane for four hours – they turned the lights off and everything, like it was going to take off.”

“But we were still sitting there,” Balciunate added. Serbejs said he fell asleep hoping to wake up in Spain, “and I woke up and we hadn’t moved”.

“We don’t even expect to go to Barcelona any more,” Balciunate said. “Maybe there’s another drone up there, but we have hope. There’s a prayer room over there, we were thinking about going.” They had been offered a hotel during their wait, but declined it because they live so nearby.

Others were more or less stranded, and couldn’t go home even if they had wanted. Renata Alinta, 50, was sitting on the floor waiting with her three sons, aged nine, eight and six, after arriving via a circuitous route from Northern Ireland. They were aiming for a flight to the Dominican Republic, where they hope to spend Christmas.

Their original flight from Belfast to Gatwick had been cancelled, but after BA said the connection to the Caribbean was still likely to depart she had paid for another flight to Stansted, then taken a cab. The detour had cost her an extra £430. Now her two younger boys were rolling about on the floor in frustration, while the eldest, who was suffering from a cold, dozed with his head in her lap.

“We’ve been waiting since 5am for information and we don’t know if it [the flight] is going to be cancelled,” she said. “This is our first holiday to the Caribbean and everybody is upset … There are no places to sit, so we are just relaxing. We can’t even get food because people are sitting down in all the cafes.”

Facebook Twitter Pinterest A passenger takes a nap on the floor. Photograph: Dan Kitwood/Getty Images

By the early afternoon, Gatwick’s coffee shops were beginning to run out of food, yet remained full of dozens of weary travellers. Groups clustered around power points, some laughing and joking in solidarity, others staring into glowing portals of escapism. Staff appeared swamped. Much of the misery in the south terminal was centred on a near 300-yard, slowly moving queue for an information desk.

Rebecca Dahl, 20, from Copenhagen, was about three-quarters of the way to the front, having been queuing for three hours. Her flight was expected to depart at 6am on Friday but she was desperate to rebook her flight with Norwegian Air. “I’m hoping there’s another one that’s earlier because I have no place to stay and I don’t have any money,” she said. “Maybe they can hook me up with a hotel or something.”

Play Video 1:29 Gatwick reopens after more drone disruption – video report

Maria Vega, also 20, who was hoping to fly with Norwegian to Las Vegas to go home for Christmas, said she had been waiting in the queue for about 70 minutes and had moved just 30 or 40 feet. Her flight had been delayed for eight hours. “Patience is a virtue – that’s what my mum tells me, but I think I’m going to crack by hour five,” she said. “It’s just waiting here then having to go on an 11-hour flight.”

By the afternoon crowds in the north terminal were beginning to thin after easyJet cancelled all its shorthaul flights. Rajiv Mandve, 40, and his wife and daughter had been hoping to travel with the airline to Gibraltar but were sitting on the floor waiting for a cab home to Slough.

“We waited in a queue for about three-and-a-half hours,” he said. “After that we went to another desk to get some other flight where we waited for about two-and-a-half hours – and there was only one lady helping.” The chaos had left them about £300 out of pocket. But travel insurance wouldn’t pay, Mandve said. Drones were not covered by the policy.