The first children's hospice to be built in Sussex is to be opened officially on Tuesday.
An appeal was launched to raise money for the hospice in 1999
Chestnut Tree House, near Arundel, cost more than £5m, which was raised after an appeal was launched in 1999.
It is hoped hundreds of children who in the past had to travel to Kent, Surrey or Hampshire for care will benefit from the facility.
Princess Alexandra is due to open the state-of-the-art hospice which includes areas for children and their families, a multi-sensory room, a music room and a hydrotherapy centre.
Hugh Lowson, chief executive of the hospice, said:
"Chestnut Tree House is planned to be a home from home for the children.
"It is an environment they would expect in their own home.
"It is not a hospice in the true sense of the word - it is really a home for the children and their famiies."
More than £1m will need to be raised every year to keep the hospice running.
Land for the building was donated by the president of St Barnabas' Hospice, in Worthing, Lady Sarah Clutton, on a 125 year lease with a rent of 12 mixed lilies and a brand new £1 coin to be given to her on her birthday every year.