Pilgrims numbers were down on the millions who attended before the pandemic took hold, and there were only a few pilgrims from outside Iraq, most from neighbouring Iran or from Pakistan.

Ashura commemorates a defining moment in the birth of the Shiite branch of Islam that is the majority faith in both Iraq and Iran.

It marks the killing of the Prophet Mohamed's grandson, Imam Hussein, by troops of Caliph Yazid in 680 AD in the Karbala desert.

Pilgrims traditionally walk to Karbala, sleeping in roadside camps set up along the way, in summer temperatures that regularly top 45 degrees Celsius (113 degrees Fahrenheit).

In the run-up to Ashura, mourning rituals are also held in Shiite cities and neighbourhoods across Iraq.

In Karbala, the most zealous flagellated themselves with flails or blades until their heads and backs were raw and streaming with blood, a practice frowned on by Shiite spiritual leaders.

- Divine providence -

For the faithful, religious devotion far outweighs any concerns about Covid infection.

Even though only a little over five percent of Iraqis have been fully vaccinated against Covid, pilgrims insisted they had no need of masks, counting on divine providence to protect them.

"Our belief protects us," said one unmasked pilgrim, who had travelled to Karbala from the southern city of Kut.

"We're not bothering with masks, because our faith in Imam Hussein protects us from everything," said the pilgrim, who gave his name only as Dholam.

Another unmasked pilgrim, Kamel Mohammed, from the southern city of Basra, said he too was trusting in God.

"I have great faith in God," he said. "I follow the example of Imam Hussein."

Large crowds of pilgrims began gathering around Imam Hussein's golden-domed mausoleum in the heart of the city from Wednesday evening.

Drummers banged out the rhythm, as the faithful chanted prayers and poems commemorating Hussein's martyrdom.

- Super-spreader? -

Before the pandemic, the main Shiite pilgrimages in Iraq were among the largest religious gatherings in the world, and there have been concerns they could act as super-spreading events.

Indian health officials have said that the Hindu pilgrimage of Kumbh Mela, an event held every three years that drew millions to the Himalayan city of Haridwar in January, may have helped fuel a surge in infections earlier this year.

Currently Iraq is registering about 10,000 new Covid cases a day in its population of around 40 million.

Recorded deaths from Covid since the start of the pandemic number a little under 20,000, according to health ministry figures.

The assistant director of the Imam Hussein mausoleum, Afzal Shami, insisted steps had been taken to avoid a major outbreak among pilgrims.

"Masks have been provided for visitors and anyone else who needs them for hygiene purposes," Shami said.

"Mobile teams have been deployed around the holy places to keep them sterilised and reduce the risks."

Disinfectant dispensers had been installed at the entrances to the shrine, lit up in red to draw attention. But there weren't nearly enough of them for the vast crowds camped outside.

"It's down to individual citizens to protect themselves by adopting preventive measures," Shami said.

Even before the Covid-19 pandemic began early last year, security was tight for the Shiite pilgrimages for fear of attack by Sunni extremists inspired by Al-Qaeda or the Islamic state group, which regard Shiites as heretics.

Roadblocks were again set up this year on all roads into Karbala, and access to the city was closed off completely from Wednesday.

Abbas, a pilgrim in his 60s, who spent Wednesday night inside the mausoleum, said it was the price of religious duty.

"This night comes but once a year," Abbas said. "You have to make sacrifices to perform the rituals."