Britain's military leaders of the future are being put to the test on one of the biggest training areas in the UK.
Forces Network has been given exclusive access to the 31,000-acre site at Sennybridge in Wales.
Our cameras have been following 7th Parachute Regiment, Royal Horse Artillery (7 Para RHA) soldiers aiming to become Junior Non-Commissioned Officers (JNCOs).
The troops, who are striving to become lance bombardiers, face challenges ranging from dealing with freezing, wet conditions to taking on arduous assault courses.
Bombardier Andrew Cousins said: "We're here to oversee them and keep them motivated.
"[We] try and promote command abilities [and] leadership abilities. It's all about getting them to motivate themselves to perform."
Captain Phil Wright, the officer in charge of overseeing the course, said:
"We bring them here to Sennybridge because the arduous terrain and unpredictable weather provide a challenge for them that's difficult to mimic elsewhere."
After taking on the assault course, the soldiers ready themselves for the 'Brecon Mile' while carrying Bergen and rifle.
It's a long, hard slog and also a nasty surprise - as the soldiers have to climb hundreds of feet over a distance which in fact lasts over two miles.
Captain Wright said: "We're looking for the blokes to display all the qualities we'd expect of junior commanders.
"We're looking for them to search deep inside themselves when it's particularly hard, particularly cold, wet and miserable, to rally themselves, rally those around them.
"[We want them to] display those qualities of courage, mental and physical robustness and ultimately display to us that they are capable of leading soldiers in high-stress situations."
The course is not a pass or fail one but it gives participants and leaders the knowledge to know who is ready and who needs a bit more time.
Bombardier Cousins said: "It's all a learning curve. I myself have been through it... Obviously, at the time you're not particularly enjoying yourself.
"[But] you learn from the experiences [and] you come out of it a better person and junior leader."
After taking part in the course Gunner Benjamin Crane told us:
"It was an amazing feeling to know that my section worked hard and we all came through [and] finished it together."
Gunner Connor Harris said: "That was hard. The obstacle crossing you're just in and out of water.
"It just takes it out of you, fatigues you straight away and you get the element of surprise [with the Brecon Mile as well]."
But this day of physical activity is just a part of this course.
Keep your eyes on Forces Network and Forces TV (Sky 264, Virgin 277, Freesat 165 & Freeview 96) on Thursday, when we'll be on patrol with the gunners as they face further challenges from the Welsh countryside and brush up on their basic soldiering skills.