Doraemon: Nobita and the Knights on Dinosaurs (1987)
Original title: 映画ドラえもん のび太と竜の騎士
Doraemon: Nobita and the Knights on Dinosaurs is a 1987 Japanese-language animation movie directed by Tsutomu Shibayama, with a running time of 1h 39m. It stars Nobuyo Oyama, Noriko Ohara and Michiko Nomura.
Nobita tries to prove to Doraemon and his friends that dinosaurs are still alive, and, after finding an underground cave, discovers a hollow earth civilization of knights and saurian steeds that Suneo must be rescued from.