A £4m redevelopment of a World Heritage Site has been approved by Gwynedd Council planners.

The project at Caernarfon Castle will see the creation of a new cafe as well as a lift and viewing deck opening up never before seen areas to paying visitors.

Plans for the first phase were approved last year, but Thursday saw Gwynedd Council’s planning department approve the second phase, which will also open up parts of the castle that are currently inaccessible – including the windows overlooking the town.

The project had gained the support of Caernarfon Town Council, but planning officers did not agree with town councillors that the refreshment facility within the castle would have an undue adverse impact on cafes already established in the town centre.

The report said: “Comments have been received expressing concern on the creation of another café that would compete with others within the town.

“However, a response was received from the agent stating that the intention would be to work with local businesses, and to offer a local café [the chance] to run the café within the castle, as has been done at other Cadw sites.

“It is felt that this would be fair, as well as boosting the local economy and community.”

According to Cadw, which submitted the plans, the project is set to be one of their largest and most complex to date, having selected Rhyl-based Grosvenor Construction following an open tender process.

Renovations are due for completion in early 2022.

Deputy minister for culture, sport and tourism, Lord Dafydd Elis-Thomas, added: “I greatly welcome this announcement, which marks a positive new chapter for Caernarfon Castle and its visitors.

“Making Wales’ past more accessible to people from all walks of life is vital, and through innovative technology, we can unlock unexplored areas of our historic sites while delving deeper into their histories.

“I would like to thank Cadw’s members and visitors for their continued support, which has helped us care for our precious historic buildings during this difficult time.”