The groups traditionally take part in a St George's annual parade in London
Air, Army and Sea Cadets from London have marked the 150th anniversary of the cadet movement with a St George's Day parade in Whitehall.
More than 100 cadets took part in the parade, which was followed by a ceremony at The Cenotaph.
The Cadet Corps was formed in 1860 to increase the UK's fighting force after heavy losses in the Crimean War.
They have since evolved into voluntary organisations, offering young people opportunities to develop themselves.
The cadets are sponsored by, but are not part of, the armed forces and there are currently 131,000 members across the UK.
The groups traditionally take part in the Royal Society of St George's annual parade in London.
Maj Angie Richardson said: "Being in the cadets... gives young people the opportunity to participate in challenging, fun and, most of all, safe activities.
"It's inspiring and they can achieve a great deal from personal achievement to qualifications and it embraces teamwork and the cadet forces help develop leadership and confidence."
She added: "In London as a whole, we have around 3,500 cadets and about 450 adult volunteers.
"It's different from the Scouts as the training follows the Army proficiency syllabus - this relates to military training, from map and compass, to field craft training and also embraces adventure training and community work."