The new station was built by volunteers and local contractors over three winters at a cost of £1.3 million.
Schoolchildren from Ysgol Cefn Coch in Penrhyndeudraeth and Ysgol Eifion Wyn in Porthmadog will also attend the ceremony.
1145 - Edwina Hart and Lord Dafydd Elis-Thomas board the train at Pont Croesor Station
Children from Ysgol Eifion Wyn perform and sing at Harbour Station
Children from Ysgol Cefn Coch board a special train at Minffordd Station, arriving at Harbour Station ten minutes later
1210 - Train carrying the Minister arrives at Harbour Station
1220 - Speeches
1230 - Minister introduced to key volunteers involved in the project
1240 - Minister given guided tour of new signal box
1255 - Minister declares the station open by operating the signal allowing an FR train to enter the station
1310 - Minister and invited guests travel by special vintage train hauled by Prince, the world’s oldest working narrow gauge steam loco, to Boston Lodge Halt for lunch, where plans for the new station at Caernarfon and improvements to Boston Lodge Works will be on display.
Why not come along and enjoy the festivities?