The Mysterious Beyond is a commonly recurring location in The Land Before Time. As the name implies, it is the land beyond the Great Valley that is shrouded in mystery. While it is certain there are many Leaf-Eaters in the Mysterious Beyond, they are very rarely seen and Sharpteeth are extremely common. Most of the Mysterious Beyond is dry with few plants but more recently less barren areas have been seen. in most of the movies and many episodes of the TV series Littlefoot and his friends have to travel through parts of the Mysterious Beyond. In fact, the only movie it is not seen in is The Land Before Time VI: The Secret of Saurus Rock and in this movie, an abandoned part of the Great Valley which Sharpteeth can freely enter is shown instead.
- Areas from first film: Likely not known as the Mysterious Beyond among residents of the valley, as most came from here. As shown in The Land Before Time X: The Great Longneck Migration, it was once fertile but the leaf famine reduced most of it to a wasteland. It is unknown if it has recovered.
- Skeleton Area: Seen in The Land Before Time II: The Great Valley Adventure and The Land Before Time III: The Time of the Great Giving. A vast area of skeletons and stagnant water, it contains the basins that water flowing towards the Thundering Falls was trapped in. It is located on the other side of the Great Wall.
- Desert from IV: A desert littered with jutting rock formations. Beyond it is a lake with waterfalls pouring into it and a line of mountains filled with caves bordering the Land of Mists.
- Desert from V: A desert area that stretches from the Great Valley to the Big Water. The film states that locusts desolated the landscape, but this would mean there were never any trees as no woody remains were found.
- Smoking Mountains: A group of volcanoes just outside the valley. The only known named one is Threehorn Peak.
- Desolate area: A wasteland similar to that of the original that appears in The Land Before Time VIII: The Big Freeze, The Land Before Time XI: Invasion of the Tinysauruses, The Land Before Time XII: The Great Day of the Flyers, The Land Before Time XIII: The Wisdom of Friends and some episodes of the TV series.
- Area from IX: A lush area with a river running through it from the Great Valley to the Big Water.
- Area from X: A varied area that is mainly fertile. It stretches from the Great Valley to the Longneck Crater.
- Area from XIII: Mostly comprised of plains, located beyond the desolate area. Leads to the mountains surrounding Berry Valley.
- Jungle area: A lush forest just outside the valley. Appears in some episodes of the TV series.
- Desert from XIV: A dry, sandy shrubland peppered with large, stone formations that stretches from the Great Valley to the Fire Mountain. The area resembles the deserts in the southwestern United States, and is occasionally hit with sandstorms.