After the terrorist attack on London Bridge in early June, the city erected barriers to protect pedestrians from traffic at several bridges, including Westminster Bridge. (Andy Rain/EPA)

“Are you nervous?” a security guard asked me.

I was in London and the gentleman in the fluorescent safety vest had just inspected my bag and wanded my body from shoulders to ankles, front and back.

“Should I be nervous?” I responded.

Anyone beyond the picture frame might assume that we were discussing the current climate in London. I had arrived in the British capital less than a week after a man attacked a mosque and three weeks after a trio of terrorists rammed their van into pedestrians on London Bridge and fatally stabbed eight people in Borough Market. Nerves were raw.

But anyone suiting up next to me — vest, boots, harness — would know the real reason behind his question. I was about to climb to the pinnacle of the O2, an entertainment venue. In any circumstance, 174 feet is a long, painful drop. For the next 90 minutes, all I could think about was staying vertical.

Tourists are resilient souls, but we are also cautious. After the March knife attack outside Parliament and the Manchester bombing in May, Bernard Donoghue, director of London’s Association of Leading Visitor Attractions, said that the organization noticed a slight dip in visits to central London attractions. But overall, the numbers are strong: an 8 percent increase compared with the same period last year.

In addition, he said, following an incident, typical tourist behavior usually resumes after several days.

“Recovery after the London Bridge attack was within five, six, seven days,” he said. “It hasn’t had a lasting impact.”

VisitLondon and VisitBritain also chimed in with encouraging figures. The tourism offices shared the findings of ForwardKeys, which analyzed booking data from this year and 2016. The research company discovered a 19 percent increase in arrivals from the United States to the United Kingdom during the peak travel months of June, July and August.

“London remains a safe city to visit,” said Laura Citron, chief executive of London & Partners, which runs VisitLondon, “and people should be reassured that there is an increased police and security presence around London and at the city’s visitor attractions.”

A sign posted in a storefront at Borough Market calls for information about the June attack. A reflection of the Shard, the tallest building in Western Europe, appears in the glass. (Andrea Sachs/The Washington Post)

After the Manchester attacks, the British government raised the threat level to “critical,” the country’s highest. Four days later, the danger level dropped back to “severe,” the new normal since August 2014. The Armed Response Officers retreated to the background, and the Metropolitan Police Service, whose members mainly wear stab-resistant vests and carry extendable batons, returned as the most visible presence on the streets. Attractions bulked up their personnel and expanded security checks. The next month, following the London Bridge tragedy, the city erected steel barriers at several expanses, creating a line of defense for pedestrians.

“We have a history of dealing with security issues,” said Donoghue, evoking the troubles with the Irish Republican Army. “The British have a charming, reassuring attitude. We want to live our lives defiantly and deliberately.”

But what about the foreign visitor whose lip is more quivering than stiff? In these jittery times, can a tourist loosen up and plunge headfirst into one of the world’s top summertime destinations?

Last week, I crossed the Atlantic to find out if an American in London could keep calm and carry on.

Be prepared

Before setting off for London, I reached out to International SOS for some safety tips. I wanted to update the old saws “Be aware of your surroundings” and “If you see something, say something.” For example, in light of recent events, should I avoid concert halls, bridges, outdoor markets?

Matt Bradley, a regional security director, started the counseling session with a reality slap in the face. He reminded me of the greater threats to travelers, such as petty crime, traffic accidents and gastrointestinal revolts.

“Terrorism remains a low risk to travelers,” he said, “but the increase in attacks, especially in Western Europe, has raised the profile of terrorism for all travelers.”

Instead of avoidance, he recommended preparation.

“Any location could be a target,” he said, “so knowing how to respond in case of an incident is the most important concept.”

In practice, this means . . .

●Identify a safe location, such as a nearby hotel, where you can seek cover in the event of an attack.

●Keep your phone fully charged, and bring a battery pack as backup.

●Carry a minimal amount of items when out exploring.

●Assemble a list of emergency contacts, such as phone numbers for the embassy, your hotel, insurance company and family members.

●For official information, follow the social media accounts of the local police and other emergency service providers.

● And above all, remain calm.

“The ability to think clearly is key to responding to an incident,” Bradley said.

Wrapped in a shawl of tranquility, I boarded the flight to Heathrow. I was so Zen, in fact, that I slept through a medical emergency on the plane. My seatmate, Clement Williams, filled me in on the details. While on the topic of crises, I asked him if he had any reservations about traveling to London.

“The attacks did influence my decision a little bit,” said Williams, who was spending a month in London and Paris before starting college in North Carolina. “But maybe because it’s become somewhat normalized, it was less of deterrent.”

Williams said he would probably avoid big tourist attractions, such as the London Eye, but not for safety reasons: Visiting major sites is not his style. Instead, he planned to hang out with friends and attend a soccer conference.

I asked him if his parents were worried. He said they had warned him about pickpockets. But his best friend’s mother rang louder alarms.

“She gave him all of those mom reminders,” he said, “like being cautious in big crowds.”

Mobs of people are inevitable during London’s peak tourist season, even out of the gate. After disembarking the plane, an American couple and I squinted to see the end of the mouse maze. More than an hour later, an immigration officer stamped my passport.

I expected longer queues at the top attractions, due to enhanced security measures, and packed accordingly. I filled a small bag with a few essentials and opened it on command.

“People are prepared to show their bags,” Donoghue said, “and are readily expecting it and feeling reassured.”

Tourists gather in Parliament Square, within sight of Big Ben, the day after the attack on London Bridge and in Borough Market. Several of the major attractions have increased their security measures, such as checking all bags and installing metal detectors. (Chris Ratcliffe/Bloomberg)

After the Manchester attack, Kensington Palace amped up bag searches. Before, the royal residence required guests to check oversized carriers and deep backpacks, in part to protect the exhibits. Now, the staff inspects all totes at every entry point, including the Palace Cafe.

On a rainy Wednesday, I coasted right up to the table.

“Do you have any sharp objects?” an employee stylishly dressed in black asked me.

She peered into my bag and wished me a pleasant visit.

A father and mother with two children approached. She checked the little girl’s butterfly-shaped backpack. Her younger brother appeared on the verge of tears. His father explained that he too wanted his bag searched. The woman peeked inside his Nemo pack.

“Everything’s fine in there,” she said to the youngster. “Thank you very much.”

The level of screening varied slightly among sites. At the Tower of London, a man squeezed the bottom of my bag and briefly gazed inside it. At the Victoria and Albert Museum, the guard shined a flashlight into its dark recesses. To access Hutong restaurant on the 33rd floor of the Shard, I had to walk through a metal detector and send my bag through an X-ray machine. I also had to dress “smart casual”; athletic or beachy attire could result in expulsion.

I experienced the heaviest security check at the O2, the concert venue and dining destination. All visitors are funneled through one door surrounded by a forest of security guards. Machines X-rayed people and things. On the other side of the detector, I was greeted by the snuffling nose of a bomb-sniffing English springer spaniel. I curbed my impulses and let him do his job.

As I zigzagged my way around London, I heard the birdsong of American accents and not one impatient chirp about the security checks.

Outside the Tower of London, I met a group of Maryland high-schoolers relaxing during a brief break in their hectic four-country itinerary.

The company, EF Educational Tours, had told the nearly 40 participants that they could opt out of any attractions they didn’t feel comfortable visiting. The tour operator also scotched all travel by Tube, transporting the students, parents and teachers by coach instead.

“I was a little nervous and on edge,” said Liliana Barrera, 17. “But I didn’t feel like I was going to get attacked.”

Joanie Mayle, a parent, recognized the upside of visiting London in the aftermath of a terrorist attack.

“It’s better to come now,” she said, “when security is higher.”

Exhibit extravaganzas

The attacks aren’t crimping Princess Diana’s style; the Kensington Palace exhibit, “Diana: Her Fashion Story,” is sold out through early August. Nor have they silenced Pink Floyd. Since mid-May, the Victoria and Albert Museum has sold more than 155,000 tickets to the “Pink Floyd: Their Mortal Remains” show, which closes Oct. 1. In addition, instead of retreating into its fortress, the arts and design institution has become even more accessible and available to the public.

The attacks aren’t scaring off fans of Princess Diana. Tickets for the “Diana: Her Fashion Story” exhibit at Kensington Palace have been selling out this summer. (Daniel Leal-Olivas/AFP/Getty Images)

More than 155,000 people have attended “Pink Floyd: Their Moral Remains,” at the Victoria and Albert Museum. The exhibit ends with a surround-sound experience of the band’s concert footage and videos. (Andrea Sachs/The Washington Post)

Last week, the V&A unveiled the Exhibition Road Quarter, an extension with a porcelain-tiled courtyard, cafe, visitors’ center, gallery and gift shop. The new entrance, once a forbidding stone gate, draws in pedestrians along Exhibition Road, a cultural thoroughfare with science and natural history museums and academic centers.

“It wasn’t a welcoming face to the space,” Lucy Hawes, a press officer with the museum, said.

Now, guests step through a big, gaptoothed smile.

During my forays, I found it easy to distance myself from recent events. Staring at the royal jewels inside the Tower of London, I thought about whether the Imperial State Crown, which weighs as much as a sack of sugar, gives Queen Elizabeth II a headache. I wondered if the wool tweed suit Princess Diana wore on her honeymoon was hot and itchy. I lost myself in the music of Pink Floyd and loudly murmured a song or two while inside the headphone bubble.

“You can tell the Americans,” said my friend Tim Wilson, who came down from Newcastle for the day. “They move their heads to the music. The English would never do that, unless no one was looking.”

But I couldn’t escape for long, nor did I want to. I felt a sense of responsibility to reflect on the attacks and offer my sympathies to the victims, even if there were no ears to receive my words. My urge to reach out and connect, I learned, was a common response.

Over coffee at Somerset House, Donoghue told me that foreign and domestic visitors were approaching tourist information centers to share their grief and express solidarity with the residents of London and Manchester. He suggested that I walk over London Bridge and venture into Borough Market, a honeycomb of food purveyors and pubs.

“It taps into a great well of feeling,” he said.

On a weekday evening, I joined the flow of commuters traversing the expanse over the Thames. As they continued onward, to their homes or happy hours, I stopped midway at a shrine to the victims. Friends and family members had taped photos and messages onto the wall and placed candles, flowers and flags on the ground. Several people had left skateboards, a tribute to Ignacio Echeverría, the Spaniard who had attempted to rescue a woman by fending off a terrorist with his skateboard.

“Hope you are skating up there in the clouds,” one note read.

At the terminus, an illuminated board urged anyone with information about the attack to call the hotline. Signs in storefront windows broadcast their love and support of the neighborhood and shared websites accepting donations for the victims. Restaurants advertised discounts to first responders.

Students’ paper hearts are strung along a wall near London’s Southwark Cathedral as a makeshift memorial for attack victims. In their handwritten messages, the children express their love for London and wish for peace. (Andrea Sachs/The Washington Post)

At Southwark Cathedral, paper hearts created by schoolchildren adorned a stone enclosure. The glitter sparkled and the tissue paper rustled in the breeze as the church bells rang and the revelers raised their pints in an evening toast.

‘We’re covert, not overt’

In my hotel lobby, I searched the faces — American business executives, Muslims celebrating the end of Ramadan, Adele concertgoers — for my English friend. I found Tim near the concierge desk, slightly disoriented after a Tube ride. We set off for a day of sightseeing, with a side of law enforcement.

I first met Tim in the Falkland Islands, when I had stopped by the police station seeking directions to a Pilates class. He recently returned to England after retiring from the police force after nearly 40 years. Not counting Tim, I had only seen four policemen, and no weapons, since arriving three days earlier. By comparison, on a recent trip to New York, as soon as I arrived in Penn Station, I experienced a full assault of officers slinging guns as large as elephant trunks.

“We’re covert,” he said, “not overt.”

On our stroll to the V&A Museum, we passed a few officers assisting an injured woman. They were all on foot. Tim explained that the police operate as mobile units and drop into emergencies as needed. During the London Bridge attack, help arrived eight minutes after the rampage began.

Not far from the museum, a police car had pulled over a Mercedes convertible. Several Middle Eastern men holding Selfridges shopping bags waited on the curb while an officer inspected the trunk. Tim interpreted the incident for me. Most likely, he said, the men had bought the car during their visit to London and had not purchased insurance. The police would impound car and the men would return home, abandoning the luxury vehicle. In other words, nothing to see here.

Not far from my hotel in Kensington, we ventured into the Shepherd’s Bush neighborhood to catch the Tube. A concierge had told me that we could see the remnants of Grenfell Tower, the public housing building consumed by fire in mid-June. But the trees obstructed our view. Tim, returning to his role as security commentator, pointed out the cameras installed outside a shopping center. He said they would deter any troublemakers.

“The police are right on the ball, and security is better than ever with CCTV,” he said. “Everything fits together in the bigger picture.”

We boarded the Tube to the Notting Hill Gate station, where we would part ways. As we rode the escalator from the depths of the Underground and followed one of its tentacled arms to my platform, Tim asked me, “Do you feel safe?”

I said I did, but I didn’t believe it until several minutes later. On the train, the cars suddenly stopped. No one peered anxiously out the window or shifted in their seats.

I waited several minutes before the conductor’s voice came over the PA. In a pleasant lilt, he apologized for the inconvenience and informed us that he was looking into the matter. He quickly returned with the cause of the delay. Congestion, just as he suspected.

Yes, Tim, I feel safe.

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