THE main gate at Portsmouth Naval Base will be closed throughout February to beef up security.
Unicorn Gate, off Market Way, will be updated with an automatic vehicle plate number recognition, new signs and an electronic information screen.
This is the largest update on the naval gate security since the Trafalgar Gate three years ago, other updates have also been made to the jetty security since then.
A naval base spokesman said: 'We do not envisage an attack but are always keen to update our security measures, it is almost a constant job.'
The Trafalgar Gate, off the M275, will remain open 24 hours a day to ensure vehicle access.
Visitors arriving on foot can use the Unicorn Gate as usual, as well as Trafalgar Gate and Victory Gate at the Hard.
Opening times at Malborough Gate off Queen Street are being extended to minimise congestion and Hampshire police, along with Portsmouth council will provide signs warning drivers of the changes.