The Welsh Government has given the go-ahead for a new £66 million home for Holyhead High School.
Over 900 pupils are set to move into a new purpose-built school near the town's leisure centre by September 2030, replacing the current site on Alderley Terrace.
The plans were approved with ministers without any modifications, following a public consultation held last summer.
But Anglesey Council says the new school is dependent on financial support from the Welsh Government and is hoping to jointly fund the project through mutual investment.
Council chief executive Dylan J Williams said: "Welsh Government approval without any modifications marks an important milestone in our plans to provide high-quality, sustainable education for young people in Caergybi."
"A modern new learning environment at Ysgol Uwchradd Caergybi would ensure that pupils have access to the best facilities and opportunities available."
"These proposals also support one of the council's key strategic aims – Education – by helping to ensure effective provision today and long into the future."
Over a thousand people took part in last summer's consultation - with the vast majority (78%) in favour of building a new school.
But some argued the new site was too far away from the town centre, while others wanted the current school to be redeveloped.
The council says it will now follow the statutory planning process before construction work can get underway.
Aaron C Evans, Anglesey Council's director of education. added: "We're delighted that Welsh Government has given its seal of approval for a new building for Ysgol Uwchradd Caergybi."
"Creating a modern, purpose-built school building represents a major investment in education in Caergybi and its catchment area. We believe this project will secure the long-term sustainability of secondary education locally and provide specialist learning spaces of the highest standard."
"A new building and facilities will contribute towards ensuring the best possible experiences and outcomes for our young people, while fully supporting the council's aims of modernising learning communities and developing the Welsh language strategy."


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