Denmark’s royal family has participated in a special “celebratory church service” at Aarhus Cathedral as the new King Frederik X, accompanied by wife Queen Mary and mother Queen Margrethe, waved to crowds gathered outside the 12th-century building.

The royal family drove 3.5 kilometres (2.2 miles) through Aarhus, Denmark’s second-largest city, from royal residence Marselisborg Castle to Aarhus Cathedral, which is the tallest church in the country.

The church service came exactly a week after Frederik, 55, was proclaimed king after his 83-year-old mother Margrethe signed her abdication during a meeting with the government.

Aarhus resident Christina Elmstroem said she expects Frederik and Queen Mary to change the Danish monarchy “in their way”.

She brought her children to experience the “big, major event”.

“So, it was an opportunity to go and see the new king and my kids are very excited about it,” she said.

Henrik Wigh-Poulsen, bishop of the Diocese of Aarhus, told The Associated Press they had just a few weeks to plan the service, and Frederik had a hand in planning it.

“Normally, you would spend three months planning this, but we (had) two-and-a-half weeks, something like that. So we have been very busy, I tell you,” he said.

“I chose some of the hymns we’re going to sing, and the king said, I would like to sing these hymns.”

The hour-long service marked Frederik’s first official visit as king outside the Danish capital Copenhagen.

Police expected around 70,000 people to line the royal route.

“I think he’s going to be a king of the people,” said Aarhus resident Charlotte Houman.

“I think he’s gonna embrace the people … he’s going to be different in his way of ruling.

“I think he’s going to be not too much top down, but he’s gonna be embracing the people, different kinds of people.

“And also being there not on this high pedestal somewhere.”