The event took place at the grand setting of Endcliffe Hall in Sheffield.
The Endcliffe detachment of Army Cadets plan to take 60 cadets and 10 accompanying adults, to George Cross Island.
The fundraising was given a healthy start by Colonel Richard Elliott from SAFFA with a generous donation of £4,000.
Afternoon tea events are one of many planned fundraisers to be held, to help them achieve their goal.
This also includes a skydive by Staff Sgt Montgomery and another cadet.
The Lord Mayor of Sheffield was a VIP guest at the event and enjoyed the tour and afternoon tea.
Endcliffe Hall was once the private home of Victorian industrialist and philanthropist John Brown who died in 1896.
He rebuilt the hall in 1865 and it is still the largest private residences ever built in Sheffield-it originally stood in 50 acre grounds.
Staff Sgt Montgomery came up with the idea for the afternoon tea fundraising event.
“We have an excellent venue that’s not used, so it laid itself to something which wasn’t too complicated, and there are plenty of cadets. Everyone had a job to do so that was it really good.”
The event consisted of afternoon tea which was then followed by a tour of the hall and grounds, with cadets acting as guides pointing out interesting facts about this rarely seen hall and its history.
Staff Sgt Montgomery said: “The venue was excellent, the tour was really good.
“The food was lovely and provided by Blend Kitchen.
“Not only did the event help to raise £650, it’s also a useful exercise for the cadets.
“These cadets might be unsure, but if you show you’ve got confidence in them.
“It kind of gives them a little push and they're more likely to take that step, which is really good.”
Anyone interested in becoming an army cadet should visit www.armycadet.com and complete the online.
“We’re always looking for adult volunteers as well we don't have enough,” added Staff Sgt Montgomery.
The detachment aims to host another afternoon tea event on June 4 holding two sittings throughout the day.