Far, Far Away in the South (1982)

The little bear heard that south of his native place (up the river) a chestnut tree blooms in the spring. In the fall, before going into hibernation, he built a boat, intending to go in search of a chestnut tree in the spring to watch it bloom, because he really dreamed of seeing it. He met a little frog who asked to also go with him to that chestnut tree in the spring. The little bear agreed.