Who reveals more secrets from Thror's map at Rivendell?

Who reveals more secrets from Thrór’s map at Rivendell? Elrond reveals the map’s hidden information. At Rivendell, the Elf-lord examines the Dwarves’ map of the Lonely Mountain and identifies moon-letters that explain how its secret entrance can be found.

The map is not merely a drawing of terrain. Its concealed writing can be read only under particular lunar conditions, and Elrond recognizes the Elvish script and its significance. In the film, he also points out that the hidden door will become visible on Durin’s Day, giving the company a crucial deadline for reaching Erebor.

A common confusion is to credit Gandalf, because Gandalf organized the expedition and understands much of its larger purpose. Elrond, however, is the character who interprets the map’s concealed clues at Rivendell. This scene also underscores Rivendell’s role as a place where different peoples’ languages, histories, and lore can be understood.