Some of these pictures and descriptions may give away plot details that you might not want to know before watching the film.
This is a TV movie remake of the TV movie Planet Earth (1974) which was based on a Gene Roddenberry script. After a mass of asteroids reach Earth, crashing meteorites into the planet for days, Earth is nearly destroyed. Three scientists are up in a space lab working on an experiment on suspended animation when the catastrophe happens, so the space lab's computers keep the scientists in suspended animation for 180 years. When they are re-animated, they return to Earth to search for an underground location where their colleagues and family were also put into suspended animation, but with nobody to revive them. The scientists travel overland in a giant white vehicle, but the whole planet has changed and they have trouble finding the location. As they travel they meet up with several groups of survivors. The movie is in two parts. In the first part, they find a man-made jungle environment and the remnants of an abandoned zoo where the animals now live in the wild, including lions and tigers and snakes.
One of the scientists, Alison, is kidnapped and held in an old zoo cage by a band of people who live with the wild animals and protect them. In return, the lions don't eat them. The other two scientists, Tony and Dr. Scott, search for Alison with the help of a guide from a different band of men who are animal poachers. After their guide abandons them, taking their only gun, they continue searching for Alison during the night. They encounter a large number of snakes, including a cobra, crawling on old zoo cages, crawling on the ground, and swimming around in a puddle of water. Dr. Scott appears to be terrified of snakes, but he carries on as they walk through ground water filled with writhing snakes. They find a cache of tranquilizer darts and make a crossbow to shoot the darts, then they shoot one of the kidnappers and take him hostage.
The kidnappers blame Alison for lying to them and sentence her to death. They take her to the edge of a pit filled with snakes, intending to throw her into the pit so the snakes will kill her. We get a brief look at the pit full of snakes and hear the usual absurdly over-exaggerated sounds of hissing and rattling that we typically hear in a movie when we see snakes. Alison screams when she sees the snakes, but Tony and Dr. Scott suddenly show up with their hostage and demand that the kidnappers let her go in return for their hostage. That happens. Alison walks away and the poor snakes are left with nobody to bite.
We see a cobra and a gopher snake and some unidentifiable snakes in the old zoo. It's not realistic that so many different snakes would be seen hanging around in the open in one spot at night, but it's common in movies like this one. But you can find a lot of snakes in one place if you throw them in a pit like the one we see later. It's hard to tell what kind of snakes are in the pit due to the lousy video. It looks like they just rounded up anything they could find including a few large constrictors.
What I always want to know when I see snake pit in a movie is - were there really snake pits somewhere that someone used to kill people, somewhere in the real world and not just in legends and fairy tales? I can't find any information that proves they really existed. I'm not asking about snake dens. Those are real, I've seen plenty of them. My second question is - if they are real, how do they take care of the snakes? Is it someone's job to feed and water them or do they just leave them there to die of starvation? Neglecting them would not be a very good utilization of deadly snakes if you are relying on them for capital punishment. A simple rope noose would be an easier option. You might want to recommend that to your tribe if you survive the coming apocalypse.