The Pylons are small truncated square pyramid-like buildings that litter the landscape of the Land of the Lost. Pylons are often golden, tall and narrow, spaced approximately every quarter mile in a regular pattern. The surface of a Pylon is polished to a mirror-like precision and extremely smooth to the touch.
Each of the Pylons contain a matrix table filled with Crystals serving as the power source and aspect modifiers to the Land of the Lost. Nearly all Pylons have a hand-sized tetrahedral key projecting from about two-thirds of the way up one side which when turned result in a diamond-shaped opening to materialize and provide a small doorway into it. Apparently, some pylon keys can be removed from a pylon by shining reflected sunlight on them, permanently sealing the Pylon, but they can be replaced by pressing the key back to the Pylon's surface. The interior of the Pylons is an extra-dimensional black void with no discernible boundaries or surfaces and is significantly larger inside than the Pylon appears from the outside. Following the damage to the Land of the Lost, the interiors of the pylons become more defined.
Each Pylon in the Land of the Lost seems to have a different function and separate abilities. Some control different aspects of the Land, such as the movement of the Sun and the Moon, others act as time portals. So far, only a few have been identified:
- The Weather Pylon - Located in the jungle, this pylon regulated the weather conditions in the Land of the Lost. It was discovered by Will Marshall and Holly Marshall early on the their adventure in the Land of the Lost. Accidentally altering the weather, they restored the weather using the color code from the Skylons. However, the powers of this pylon are infallible as it confused the circumstances caused by the hurricane caused by Beauregard Jackson's arrival. (Cha-Ka (episode) and Stone Soup)
- The Mountain Pylon - Discovered by Will Marshall, this pylon seems to have an indiscernible purpose, but it may have power over the dimensional doorways into the Land of the Lost as it was this pylon that Will used to briefly trap Beauregard Jackson in the Land of the Lost. (Hurricane)
- The Prison Pylon - Located somewhere in the jungle, this pylon was discovered by the Pakuni and seems to hold the trapped essence of one of the Altrusians. Opening when the three moons come into conjunction, it takes possession of Cha-Ka then Holly Marshall, using them to charge up the pylon from the crystals in the area, but Rick Marshall damages it when he clears its matrix table of crystals. (The Possession)
- The Clock Pylon - Located deeper in the jungle, this pylon regulated the control of the moons in the Land of the Lost and hence could be used trap the Land of the Lost in eternal day or eternal night. This Pylon also seems connected to the power source under the ground and may actually regulate it. (The Longest Day, Blackout and One of Our Pylons Is Missing)
- The Keyless Pylon - Located somewhere in the jungle, this pylon seems to use doorways to link itself with other dimensions in a manner different than the Mountain Pylon. It also opens when the three moons come into conjunction. Ta notices this and uses it in a ceremony to get packages of food ("groceries") from Earth, but just how the Pylon realizes what Ta wants is unknown. Time inside the pylon is slower than the other pylons; Rick and Will spend several hours inside it while only a few minutes pass inside. This trait doesn't affect Holly as she manages to use it to view several dimensions, including San Francisco on Earth. (The Pylon Express)
- The Lost Pylon - Located somewhere near the Lost City, this pylon either remains invisible or is capable of moving itself around the Land of the Lost. After Will explores it, it renders him invisible for twenty-four hours. (The Orb)
- The Sun Pylon - Located somewhere near the Lost City, this is the only black pylon in the Land of the Lost. It controls and regulates the power of the sun in the Land of the Lost. The Sleestak tunnel into it to create sun flares that threaten the Marshalls as well as all life in the area. A mysterious man named William Blandings arrives to repair it. (Repairman)
- The Time Pylon - Located in the outer most outskirts of the Land of the Lost near the geyser beds, this pylon controls the time in the Land of the Lost, requiring the use of a Altrusian relic as its key to its matrix table. Jack Marshall uses it to travel back in time to save Cha-Ka as time reverses outside the pylon. However, it also seems to prevent duplicates from appearing. The time key vanishes from the past as Jack brings it back, and Jack rejoins himself, his memory of future events becoming deja vu. Unfortunately, Torchy fuses the exterior key so it can't be opened again. (Timestop)
- In Season 3, the Pylons were redesigned after many of the original sets were destroyed. The new Pylons were dull in color and the interior had clearly defined stone walls and floors with a mica-like appearance. Likewise, the matrix tables were redesigned with a stone pedestal and a grid of all-red crystals.
- In one episode The Possession, it is suggested that the Pylons were built by the Altrusians. In David Gerrold's backstory for the series, he confirms this, explaining that the Altrusians built the entire Land and everything in it as a way-station intended to let travelers cross between various places. The time doorways are gateways which allow their users to cross into the Land on their way to their destination. The reason that travel through the time doorways is unpredictable, at best, is that the Land has fallen into disrepair in the time since it was built. However, the series as presented remains unclear on this subject.