The main access road to Newborough Forest and Llanddwyn beach will be closed next month due to essential drainage work.
Anglesey Council says a new drainage system will be installed near the church to protect the highway and reduce the risk of future problems.
It means there'll be no vehicle access from Newborough village to the main visitor car park at Llanddwyn on weekdays between Monday 5th and Friday 16th October.
But the road will be reopened from the evening of Friday 9th to early on Monday 12th, with work due to be completed ahead of the half-term holidays.
The council has apologised for the disruption and the inconvenience to residents, visitors and local businesses.
Huw Percy, head of highways at Anglesey Council, said: "We fully appreciate that this closure will cause disruption and apologise for the inconvenience."
"These drainage improvements are essential to maintain this important route. We have deliberately scheduled the work during a quieter period and before the school half-term holiday to minimise the impact."
"Our teams will do everything possible to complete the work as planned and restore access to the main visitor car park as soon as possible."
Emergency service access will not be affected by the works and advance warning signs will be installed ahead of the closure.
The work is being closely co-ordinated with Natural Resources Wales, which manages Newborough Forest, to keep disruption to a minimum.
Cllr Ieuan Williams, who holds the highways portfolio, added: "We recognise how important this route is to residents, local businesses and visitors."
"These essential improvements will help protect the road for the future, and we thank everyone for their patience and understanding while the work is carried out."
Both Newborough Forest and Llanddwyn will remain open while alternative parking is available at Pen Cob, Llyn Parc Mawr and Llyn Rhos Ddu.
The council advises that using alternate car parks involve a longer walk to the beach and visitors are encouraged to allow extra time for their visit.


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