Place: why Gibraltar wants In

Since then, the European Commission has repeatedly intervened to prevent delays over the border when tensions have risen. Although Mr Picardo believes Gibraltar will always remain British, and there is no suggestion of a military threat to the Rock, he argues Brexit could embolden Spain to cause problems at the border or consider closing it and to push for joint sovereignty over the territory.

José Manuel Garcia-Margallo, Spain’s acting foreign minister, has said he would start talks on Gibraltar “the very next day” after a Brexit.

Mr Picardo said remaining in the EU would give Gibraltar “the tools to defend ourselves against a predatory Spain”.

“When the time comes, we need to ensure the United Kingdom has at its disposal as strong an arsenal of measures to defend Gibraltar as possible,” he said.

He criticised the Leave campaign for “wrapping itself in the Union flag”, arguing that it was more “patriotic” to remain a member.

“If you are a patriot, you want Britain and, with it, Gibraltar to be stronger and safer,” he added.

He said Brexit would also harm the economy, which relies on trading financial services with the EU.

Damon Bossino, a Gibraltarian whose father used to run the Art Deco Rock Hotel, and his Spanish wife, Rosa, are also concerned about a Brexit. Mrs Bossino’s elderly parents live less than a mile away in Spain and she fears more stringent border checks, or a complete closure.

“I have seen videos of what happened under Franco,” she said. “Is this going to happen to my family? It is something that doesn’t depend only on us. It depends on the UK. It is worrying.” The couple regularly drive their nine-year-old son, John, who is autistic, across the border for treatment.

“If I had to take John on a plane [for treatment in Britain], it would be very stressful for him,” she said.

Some, such as businessman John Bromfield, are convinced any Spanish threat can be seen off regardless.

“I can understand the apprehension,” said Mr Bromfield, who will be voting to leave.

“They like the protection of the EU and they wonder if Britain will step in and replace that. My view is that for the last 300 years that is exactly what Britain has done.”

Not that this calms Mr Rodriguez. Over the years, he pointed out, the British military presence here has dwindled.

“Now,” he said, in a nod to his replica uniform, “we are the ones that are defending the Rock”.