Princess Leonor of Spain must undergo military training as she braves the elements in the Pyrenees

Princess Leonor looked completely in her element as she completed military training exercises in the snowy mountains of Spain.

The royal – who celebrated her 18th birthday in October – was pictured braving the frigid temperatures in Astún this morning before hitting the slopes.

Arriving at the ski resort in the Pyrenees, the future queen was pictured wearing a zip-up camouflage jacket with the Spanish flag sewn onto the arm.

Leonor’s military uniform also consists of green pants and a matching hat.

The royal tied her long hair into a bun and tucked most of it into the back of her jacket.

She was also seen carrying a large camouflage backpack and brown suede hiking boots during the excursion with her peers.

The royal was later pictured wearing a helmet while taking skiing lessons with the group.

For this activity, Leonor was seen wearing a black helmet and skis before heading to the ski lift with her heavy backpack.

The future queen appeared particularly cheerful as she happily posed for a group photo.

The trip to the mountains is part of Leonor’s training at the Military Academy of Zaragoza.

Following in the footsteps of her father and grandfather, the royal family enrolled at the academy in August and completed a three-year course there.

When she first arrived at the academy, Leonor completed a module to help her adapt to military life – with the palace releasing footage of the royal family taking part in classroom lessons.

According to heraldo.es, she is staying in a hut with as many as twelve other students and was given basic military equipment before the first training.

During her three years at the academy, Leonor is entitled to a salary of €417 per month. However, the palace has said she will not claim the salary.

Like a boarding school, the military academy follows a strict timetable during the week. but Leonor is allowed to return home on weekends when she is not maneuvering.

Leonor graduated in May with the International Baccalaureate from UWC Atlantic College in the Welsh province of Vale of Glamorgan.

After training at the General Military Academy in Zaragoza, Spain’s equivalent of Sandhurst, she entered the naval school and completed her three years at the General Air Academy.

In July, the Princess revealed her enthusiasm to soon become a cadet at the Princesa de Girona Foundation awards ceremony in Girona, Catalonia.

She said: “I have just finished high school and am about to start a new phase with a period of military training.

“I am happy because I know how much the Spaniards appreciate our armed forces… it is an important moment in my life and I feel very excited and determined to keep learning and doing my best.”

Princess Leonor’s latest appearance comes at a particularly turbulent time for the Spanish royal family – after Queen Letizia’s ex-brother-in-law sensationally claimed to have had a relationship with the royal family both before and after her marriage to King Felipe.

Jaime Del Burgo, 53, who currently lives in Britain, recently contributed to a tell-all book on the Spanish royal family, making the far-fetched claim that they were still romantically involved after Letizia’s marriage to King Felipe in 2004.

The entrepreneur – who claims he was dating Letizia when she met King Felipe – shared an undated selfie that the Queen, 51, took in a bathroom mirror during one of her pregnancies as ‘proof’ of their relationship on X.