Four Caterpillars is the fourth episode of A Place Further Than the Universe.
The girls attend a training camp in the mountains as preparation for the trip to Antarctica. A classroom session is instructed by Gin Tōdō, then they learn orienteering, in which they must hike across the hills to reach designated waypoints. They spend the night together in a tent. In the morning Kimari finds Gin outside the tent, and they have a conversation while awaiting sunrise.
- The location of the training camp is the Norikura Highlands (乗鞍高原), Nagano prefecture.
- Kimari and Shirase attend the fictional Tatara Nishi High School.
- "Never think the stars you see are all the stars there are." - Hinata, reflecting on how they can't see the South Star from north of the equator. This is another of her made-up sayings.
- "Isn't trouble the best?" - Kimari to Gin Todo, reacting to Gin's comment about Shirase
The insert song for this episode is "Sora wo Miagete".
- Vocals: saya
- Music and lyrics: Fujisawa, Yoshiaki (藤澤 慶昌)