LONDON — With songs and silence, the tolling of bells and the privacy of memory, residents of Manchester, England, prepared on Tuesday to mark the anniversary of a terrorist bombing at a rock concert that killed 22 people and challenged the city’s resilience.
On the night of May 22, 2017, Salman Abedi, a British citizen of Libyan descent, detonated explosives packed with nails, bolts and ball bearings at a concert by the singer Ariana Grande at the Manchester Arena.
The attack was by far the most devastating in the city since 1996, when a huge truck bombing by the Irish Republican Army reduced part of the center to rubble and injured scores.
But unlike the I.R.A. bombers, who telephoned a warning of their intentions, Mr. Abedi offered no advance clues as to his plans. It emerged later that Mr. Abedi had traveled to Libya before the attack to meet with members of an Islamic State unit linked to terrorist attacks in Paris in 2015.
“Thinking of you all today,” Ms. Grande said on Twitter in a message that inspired an outpouring of affectionate replies, “I love you with all of me and am sending you all of the light and warmth I have to offer on this challenging day.”
City authorities planned a day of commemorations. Prime Minister Theresa May and Prince William, the second in line to the British throne, are set to attend a memorial service at Manchester Cathedral, during which a nationwide moment of silence will be observed. The service is to be relayed to places of worship in York, Liverpool and Glasgow.
Later, more than 80 choirs and as many as 10,000 people are expected to gather in Manchester’s central Albert Square to sing at an event called “Manchester Together — One Voice.” The singers include a choir of parents and children who were at the Ariana Grande concert the night of the bombing.
At exactly 10:31 p.m., a year to the minute after the bombing, church bells will toll across the city center.
The authorities have also planted 28 Japanese maple trees along what they called the Tree of Hope Trail, where people may leave messages to be kept in an archive chronicling Manchester’s response to the attack.
The bombing came midway through a series of attacks from March to June, most of them in London, adding Britain to the list of European countries been struck by Islamist militants. On two occasions, assailants in vehicles rammed pedestrians on bridges across the River Thames in London, deepening a sense of vulnerability.
With memories of suicide attacks and other assaults since 52 people died in a coordinated onslaught against the London transit system in 2005, many Britons have been forced to live with the threat of terrorism, even as officials assert that many more planned attacks have been thwarted. But some officials detect a more nuanced shift in the perceptions of hazard.
“Manchester has changed,” the city’s mayor, Andy Burnham, said on BBC radio on Tuesday. “We’re stronger and more together and there is a palpable sense of community spirit. But underneath the scars are very real and deep. We’re a city in recovery.”