They met members of the Central Beacons Mountain Rescue Team who guided them through the process.

The organisation is run by volunteers and responds to calls 24 hours a day throughout the year.

Prince William and Kate arrived at the national park, which recently decided to use only its Welsh name Bannau Brycheiniog, wearing hiking gear.

When asked by instructors if he had abseiled before, William said: "It's been a while."

Before heading over the edge Kate, who was wearing a red mountain rescue top like her husband, with her hair tied in a ponytail, was heard telling William: "We're not racing."

After leaving the Brecon Beacons, they then visited Dowlais RFC where they ordered pizza from a van parked outside the rugby club.

Crowds gathered in Merthyr Tydfil to see the royals amid the cold and wet weather.

Among them was nine-year-old Isla Cheek who had written a card to the couple and brought with her a bouquet of yellow tulips to give to them.

Some of the letter's content was a closely-guarded secret but Isla confirmed it included "how they inspire [her]".

"They should come to my school to visit and stuff like that," she added.

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"I think she's also asked could she possibly have Prince George's hand in marriage as well," family friend Laura Ingram added.

"We wish we could have given them a bit of a drier welcome but we're really excited that we've come to Merthyr today, just before the coronation as well.

"I just really like what they stand for. I think they're very hard-working. The causes that they support. I think it's a really important part of our tradition."