32 people were killed and hundreds wounded in the attacks at Brussels airport in Zavantem and the Maelbeek metro station
Ceremonies have taken place to mark the first anniversary of the suicide bomb attacks in Brussels that killed 32 people.
King Philippe and Queen Mathilde led sombre ceremonies at Brussels airport in Zavantem and the Maelbeek metro station, held at the exact times the bombers struck on 22 March last year.
Families of victims and survivors of the attacks were among crowds at the ceremonies, and a new steel memorial to those killed was unveiled near the European Union headquarters.
Trams and buses ground to a halt across the Belgian capital and commuters and public transport workers applauded during a "minute of noise".
More than 300 people were wounded in the attacks, claimed by Islamic State, where suicide bombers detonated explosives in the departure hall at the airport and on a packed rush hour train.
At the airport, King Philippe laid a wreath outside the departure hall. The names of the 16 people killed in the attack there were read out and a minute's silence was held.
Eddy Van Calster, whose wife Fabienne Van Steenkiste was among those killed at the airport, performed a song of reflection as the royal family looked on.
Prime Minister Charles Michel, who faced claims that Belgium was a "failed state" for not preventing the terror cells from carrying out the attacks, said the country remained strong.
He tweeted: "Today we remember the victims of the attacks. We all remain united."
At the metro station, King Philippe laid a second wreath in front of a wall covered in messages to those who were killed.
At the final ceremony, leaders including EU Council President Donald Tusk attended the opening of a new memorial to the victims - comprising two pieces of curved steel punctured with holes to look like shrapnel.
On Wednesday afternoon, three marches will converge at the Place de La Bourse, which was filled with flowers as a memorial to the victims after the attacks last year.
One of the city's most famous landmarks - the Manneken Pis statue of a little boy - will be dressed in a fireman's outfit to pay tribute to the work of the emergency services in the wake of the attacks.
Belgium has remained on its second-highest alert level since the bombings - meaning the threat of an attack is possible and likely, but not immediate.
Soldiers continue to guard key buildings and transport links and carry out random patrols in public areas.
The attacks started at the airport, where Ibrahim El Bakraoui and Najim Laachraoui detonated suicide bombs hidden inside suitcases as people queued to check in.
Ibrahim's brother Khalid set off his device just over an hour later at Maelbeek station.
Mohamed Abrini, whose device failed to go off at the airport, was arrested in Brussels nearly a month later.
Investigators have said the attacks were carried out by the same network that was behind the November 2015 Paris attacks, in which 130 people were killed.
The arrest of Paris attacker Salah Abdeslam in a police raid in Molenbeek four days before the Brussels attacks is said to have panicked the rest of the cell into targeting the airport and metro, according to investigators.