Undergrotto is truly the greatest fortress ever created. A deep, hand-carved grotto houses multiple astounding feats of engineering.

Posted here are just a few of the amazing features from the 61 page Undergrotto tour. For the brave, we host a 14 megabyte file of the entire tour by creator Retro for download here.

Download The Full Undergrotto Tour (PDF 14.8 mb)

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