The Tunnel to Summer, the Exit of Goodbyes is a Japanese light novel written by Mei Hachimoku and illustrated by Kukka, published by Shogakukan under its Gagaga Bunko imprint in July 2019. A manga adaptation, titled The Tunnel to Summer, the Exit of Goodbyes: Ultramarine and illustrated by Koudon, was serialized in Shogakukan's seinen manga magazine Monthly Sunday Gene-X from July 2020 to November 2021, with its chapters collected in four tankōbon volumes. Both the light novel and manga are licensed in North America by Seven Seas Entertainment. An anime film adaptation produced by CLAP premiered in September 2022.