This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Keywords from Image Description:
General view of Grotta Gigante from the exit stairs. en This is view of the main chamber of Grotta Gigante near the end of the guided route after going up long stairs The two vertical plastic tubes are surrounding one very long pendulum each one for scientific purposes es Esta es una vista de la cmara principal de Grotta Gigante