In celebration of the series' 30th anniversary this year, Nintendo has released a new look into the development of the very first The Legend of Zelda game for the Nintendo Entertainment System.

Shown off in documents and a video, it's revealed that the skull room and secret passage are both designed by Takashi Tezuka, whose sketches look very similar to what fans find in the final product of the game.

Map drawings by Shigeru Miyamoto were shared as well, complete with notes and tree doodles. The video showcases a sweeping shot of the game's overworld, showing the title's sequence of events and places where the player might encounter an item or trigger a musical jingle.

Though not much else was shown or explained, it's interesting to see the raw origins of one of video game's most popular franchises and witness about how far the series has come since then. Its latest entry, The Legend of Zelda: Breath of the Wild, releases for both the Wii U and Nintendo Switch next year. Two new concept images of the game were shared last week, and some footage of it in action can be found here.

All of the images and the video shared today can be found below: