"(Up A) Lazy River" is a popular tune and song by Hoagy Carmichael and Sidney Arodin, published in 1930. The melody is by Arodin, arranged and with words modified by Carmichael. It is considered a jazz standard and pop standard, and has been recorded by many artists. A bit of the song is played by Carmichael in the 1946 Oscar-winning film The Best Years of Our Lives.
The song was stored in music box format in a permanent outdoor display in Cathedral Park under the St. John's Bridge in Portland, Oregon.