Land of the Lost opens with a toe tapping, banjo accompanying song describing the thrills and chills of the Marshall family. An earthquake sucks their raft down into a giant hole, which was really a portal into another dimension, the land of the lost. There, they find all sorts of things that should be, all assembled into the same place. In all of that, they do their best at being a family. They live in a cave up high off the ground, which they called High Bluff. They discovered and named dinosaurs galore, the most famous being Grump, the T-Rex that chases everything and roars into the cave to swell.
The family itself contained Dad, who had a name that didn't matter, Will, the teenage boy, and Holly, the gradeschool girl. Their sometimes visitor was Chaka, a humanoid called a Pakuni, who befriended them when they found the land. Chaka could speak Pakuni very well, but he was very bad at English.
The show wasn't just trash, either. This was full-blown juvenile SF. It featured a collapse alien civilization that had made the land, the last of whom was Enoch, the Altrusian. Their descendents, now nocturnal, are the Sleestak, taking every opportunity to terrorize the family. The land itself is runy by pylons which utilize the Altrusian crystal technology to regulate the sun, moon, weather, and even portals into other worlds.
The first series itself was designed as a loop, so that the last episode directly took you into the first. How cool is that?
Heaven isn't forever, and neither are perfect shows. After two seasons, Dad Marshall had enough of the show and the cave set for High Bluff burned down, so the family moved into a temple near the Forgotten City, trading Grumpy for an allosaurus name Alice and too many Sleestaks as neighbors. The great conflaguration that swallowed dad conveniently brought in Uncle Jack, who was a congenial fellow, but nowhere near as cool as Dad was. (Dad had a certain intensity and daring in the face of necessity that made you really admire him.) Chaka now spoke English pretty well and lost his family. They even got a few more creatures, such as a fire-breathing dimetridon. All in all, the third season was meh.
After filming enough episodes to go syndicated, Land of the Lost move to the weekdays and the magically profitable land of weekday repeats. Nothing as cool replaced it on Saturday morning.
Land of the Lost was not without competition. There was also the cartoon show The Land that Time Forgot or something like that, about a place with dinosaurs and cave men. Again, people got lost and wound up there. It wasn't nearly as good or as compelling, but if you wanted a dino fix, it did fill that niche.
Sid & Marti Croft tried to revive Land of the Lost in the 90's with a passable show. It wasn't nearly as fun as the original, but not nearly as bad as critics panned it. It was more passable than anything.
Will Ferrall bastardized the whole thing into a Will Ferrall movie, and you can guess how well that worked out. Will Ferrall is a "comedian" who produces "comedies." Personally, I think that he sleeps with all the financers. Gotta make all those little old ladies happy, right? Make a bad movie, then walk away with the profits.