Foreign (non-US) film about a boy who travels back in time during a a school trip into the mountains, and saves a village

Question

The film was a foreign film (Eastern European?) produced I think in the 2010s. The film was about a teenage boy who is terrified of heights. On a school trip into the mountains he somehow travels back in time. (There was an eclipse. He gets sucked into a hole that opens in the mountain.)

Eventually, he saves a village (by helping with a flying machine?). Strong fantasy elements that I think are connected to legends/history from the country where the movie was produced. Anyways, after he defeats his fear he goes back into his time and saves his friend who is falling and is in mortal peril.

Answer 1

The Stronghold (2017). It's a Ukraine film.

The Stronghold is a Ukrainian adventure/fantasy film based on the same-name book. A present-day schoolboy Vit'ko goes a thousand years into past.\

Trailer

The trailer mentions the eclipse, show Vit'ko being transported back in time (to 1120 AD), mentions that the MacGuffin is an artifact that is a "source of infinite power", and shows some stone golems fighting, which further supports the fantasy aspect.