Now, squeezed between a woman who never stopped chatting to her friend on the other side of the aisle, and a man who clearly enjoyed making it difficult for him to turn the pages of the Times, Giles reflected on what he hadn’t missed. The two-and-a-half-hour flight seemed interminable, and when they landed he had to dash through the rain to get to the terminal.

Although he was among the first off the plane, he was almost the last to leave baggage reclaim. He had forgotten just how long it could take before your luggage appeared on the carousel. By the time he was reunited with his bag and had been released from customs and finally made it to the front of the taxi queue, he was already exhausted.

“Checkpoint Charlie” was all he said as he climbed into the back of the cab.

The driver gave him a second look, decided he was sane, but dropped him off some hundred yards from the border post. It was still raining.

As Giles ran toward the customs building, carrying his bag in one hand and his copy of the Times held over his head in the other, he couldn’t help recalling his last visit to Berlin.

When he stepped inside, he joined a short queue, but it still took a long time before he reached the front.

“Good evening, sir,” said a fellow countryman, as Giles handed over his passport and visa.

“Good evening,” said Giles.

“May I ask why you are visiting the Eastern sector, Sir Giles?” the guard inquired politely, while inspecting his documents.

“I’m seeing a friend.”

“And how long do you plan to stay in the Eastern sector?”

“Seven days.”

“The maximum period your temporary visa allows,” the officer reminded him.

Giles nodded, hoping that in seven days’ time all his questions would have been answered, and he would at last know if Karin felt the same way as he did. The officer smiled, stamped his passport, and said “Good luck” as if he meant it.

At least the rain had stopped by the time Giles stepped back out of the building. He set out on the long walk across no-man’s-land between the two border posts, not in the British Embassy’s Rolls-Royce accompanied by the ambassador but as a private citizen representing no one other than himself.

When he saw the guard stationed on the East Berlin border, he didn’t need to be reminded that they didn’t welcome tourists. He entered another building that hadn’t seen a splash of paint since the wall had gone up, and where no one had given a thought for old, tired, or infirm visitors who might just want to sit down. Another queue, another wait, longer this time, before he eventually handed over his passport to a young customs officer who did not greet him with good evening, sir, in any language.