Major changes have seen the decommissioning of one historic Naval training establishment, and the creation of a tri-Service college at another.

In a symbolic gesture at HMS Dryad, on the slopes of Portsdown Hill to the north of Portsmouth, the huge gates were closed and bolted behind her ship’s company as they marched out of the base.

Moments later they were re-opened for business, as Dryad – until now the Navy’s navigation and warfare training establishment - does not officially close down until later this year.

The decommissioning ceremony saw the establishment’s commissioning pennant had been hauled down after 63 years, signalling another step towards the integrated Maritime Warfare School (MWS) at HMS Collingwood, a few miles away to the west in Fareham.

Central figure in the ceremonies was Second Sea Lord Vice Admiral James Burnell-Nugent, who is responsible for personnel issues in the Royal Navy, including training.

Giving the order to decommission the establishment, the Admiral said: “HMS Dryad holds fond memories for thousands of naval warfare trainees – myself included.

“But we’re very good at being forward-looking and positive. Collingwood is a cracking establishment, so it’s onward and upward.”

Dryad will be forever remembered as the Allied headquarters for the Normandy landings – the legendary D-Day chart showing the invasion as it stood at H-Hour on June 6, 1944 remains preserved in Southwick House, which served as Dryad’s wardroom.

The closure of Dryad was originally announced in July 2001, but a small enclave housing operations room simulators will remain on site until around 2007.

After that element is no longer needed, the whole site will be handed over to Defence Estates for disposal.

A goodwill message from the Queen was read out at the ceremony, which was led by Dryad’s chaplain, Rev David Barlow.

Among those attending were First Sea Lord Admiral Sir Alan West, retired First Sea Lord Admiral Jock Slater and several former commodores and captains of Dryad.

Admiral West was also prominent among the guests at HMS Sultan when the last group of students passed out before the establishment became tri-Service.

As of April 1 the Gosport stone frigate became home to the Defence College of Electro-Mechanical Engineering – one of six centres of expertise created as a result of a review of Defence training.

Sultan will now serve as the primary site for engineering training, overseeing schools for the Army in Hampshire and Berkshire and for the RAF at St Athan in South Wales.

The base will no longer be purely Naval, and although the Commanding Officer, Commodore Neil Latham, will remain as such, he will also have responsibility as commandant of the new college.

Royal Logistics Corps engineers already learn their trade at the extensive Gosport establishment.

As part of the changes the air engineering department at Sultan will now come under the wing of the Defence College of Air Engineering, based at RAF Cosford.

Trainees at the base should notice little difference at first, beyond a few new signs and titles to get to grips with, as the aim – providing first-rate engineers for the front line – remains the same.

At the passing-out parade under the old order, Admiral West promised the 116 students “a vital and rewarding role maintaining the vessels of the future.”

Admiral West found time to chat to some of the prize-winning students – including LMEA Neil Chapman, who won four out of seven of the course’s prizes.

Neil was recently selected for officer training and will read the final year of a BEng (Hons) degree in materials and mechanical engineering at the University of Portsmouth before going to Dartmouth in September 2005.

As a memento of his visit, Admiral West left Sultan with a universal clock in the shape of a globe, made for him by machine shop instructor Richard Shrimpton.