Sixteen people were killed and dozens more injured during two days of terror in 2017.
Spain has held several ceremonies to mark the fifth anniversary of the terrorist attacks in Catalonia in 2017.
A sombre ceremony in the centre of Barcelona on Wednesday was attended by hundreds, including the president of the region, Pere Aragonès, and the city's mayor, Ada Colau.
Officials and relatives of the victims lay wreaths in front of the memorial plaque on the Las Ramblas pavement.
Sixteen people were killed and more than 120 others injured in the attacks, which were carried out by a cell of the so-called Islamic State (IS) group. The death toll included some foreign tourists from Belgium, Germany, Italy and Portugal.
A number of institutional ceremonies were held in the country to remember the victims of the attacks, while others protested that Spain has failed to acknowledge the "silent suffering" of many since 2017.
According to a recent court ruling, more than 350 people are still struggling with physical or psychological injuries as a result of the Barcelona and Cambrils attacks.
"In August 2017, Barcelona and Cambrils suffered hatred and terror in their streets," tweeted Spanish Prime MinisterPedro Sánchez.
"Five years later, we remember the victims of these attacks with our sights set on continuing to build a future of peace. Let us continue to move forward united for freedom and coexistence."
What happened during the attacks?
On 17 August 2017, a 22-year-old Moroccan man drove a rented van into pedestrians along one of Barcelona's most iconic streets, Las Ramblas.
Thirteen people were initially killed and dozens of others injured, while a fourteenth victim died days later in hospital. After the initial rampage, the man abandoned the van and murdered another person to steal their car and flee the area on foot.
Just hours later, five other members of the IS cell carried out the second attack, 100 kilometres away in the coastal town of Cambrils. Several pedestrians were knocked down by their vehicle and a woman was stabbed to death.
The six perpetrators were all later shot dead by police, while two further members of the terrorist cell had earlier died when their workshop exploded in the village of Alcanar.
Three more men were arrested by Spanish authorities and were later convicted and jailed for aiding the terrorist cell.
One of the three suspects had revealed to investigators that the group initially planned to bomb well-known sites in Barcelona, such as the Sagrada Familia basilica and the Camp Nou stadium.