Awhile back I read a science-fiction book that took place 5000 years from now, in a world where industrial civilisation had run out of resources and collapsed, the seas had risen, and California was recolonised from Hawaii (which had returned to traditional ways).
The protagonists leaves his Havaiian-style village on the coastal isands of central California (the peaks of today’s coastal hills), and sails across the Inland Sea (which we recognise as the San Joaquin valley) on a quest. At several times he has a dream experience or vision of today’s world.
Anyone know what this book was? My google-fu seems to be lacking tonight.