Carving

From Tardis Wiki, the free Doctor Who reference

Carving was an art form in which images were engraved into rock (PROSE: Meet the Doctor) or tree bark. (PROSE: Afterword) Carvings in a cave on Crafe Tec Heydra depicted scenes from the Last Great Time War. (PROSE: Meet the Doctor)

In the tunnels of Exo III, Bernice Summerfield found carvings made in living rock which depicted a group of Great Old Ones who left their bodies at some point in the universe's distant past. These carvings were millions of years old, and were identical to older carvings on Veltroch and other planets, including Earth. (PROSE: White Darkness)