The Lizard Boat Station in Shoreham Harbour had been closed for two years while the Hove and Adur Sea Cadet Unit carried out its major improvement project.
Joining the unit, known as TS King Alfred, for the reopening last Saturday were Adur District Council chairman Carson Albury and Brighton and Hove mayor Lynda Hyde.
The official ceremony was performed by Mr Peter Field, Lord Lieutenant for East Sussex.
Ian Wright, unit chairman, said: “We are very proud of our new boating station and look forward to it providing excellent training facilities for many years to come for Sea Cadets and a wide range of other users.”
After a service of dedication conducted by the unit’s chaplain, the Rev Simon Horton, the Sea Cadet ensign was hoisted over the boat station.
Following a buffet lunch, cadets from the Unit demonstrated the use of the new Versadock facility, which means the unit can offer activities such as sailing, power boating, kayaking and rowing. Specialist training in seamanship, catering and marine engineering are also available and the unit opened a Royal Marine Detachment last year
The boat house building works cost well over £100,000, funded by grants and donations, and most of the labour was carried out by volunteers, led by unit president Peter Martin.
The unit was formed in 1942 as part of Warship Week and named TS King Alfred in memory of the thousands of Royal Navy officers who were trained in Hove during the Second World War.
It is based at the Drill Hall in Marmion Road, Hove, which it shares with the Army Cadet Force. The nearby boating station was first opened in March, 2006, on the site of the HMS Lizard wartime boat base, near Maxwell Wharf.
Mr Wright said: “The Lizard has been used for many Sea Cadet boating and sailing events and, thanks in part to it, we are now recognised as one of the leading boatwork units in southern area.
“Since our formation, thousands of boys and girls have gained from the experience of being cadets in our unit and some now have their own children in the unit.”