Bikini Bottom is located at the bottom of the Pacific Ocean, below its signature island, the Bikini Atoll of the Mariana Islands. There are many instances of evidence in the show leading to it's location as well. Bikini Bottom is placed beneath its namesake island, Bikini Atoll, in the Pacific Ocean. Bikini Bottom's location at the bottom of the Pacific Ocean is mentioned or referred to in several different episodes and the movie. Bikini Bottom is also located near some other cities such as New Kelp City, Bass Vegas, and some others.
Bikini Bottom's geography is shown as consisting of mountains, dense forests, lakes, lagoons, caves, grasslands, reefs and rivers. In the movie, volcanoes, trenches and deserts are shown in the surrounding region. Major geographic features have colorful names including Sand Mountain, Jellyfish Fields, the Kelp Forest, Goo Lagoon, the Sea Needle, Rock Bottom, and a few others.
In every episode in which the skyline of Bikini Bottom is shown, features such as buildings, houses and an anchor can be seen. In earlier episodes of the series, a red flower arch can be seen, which no longer appears in the skyline. In some episodes, a lighthouse appears in the skyline, most likely in Mrs. Puff's Boating School. Other episodes feature the Krusty Krab's Marquee. A large clam-shaped structure, most likely a propeller from a ship, is seen in some episodes. In the center of Bikini Bottom, the citizens work and live in large, gray buildings made of metal. There are some other forms of buildings, mostly aquatic-themed as seen above. Further out from the town citizens need to use whatever is available and easy to live in, such as Patrick's rock, SpongeBob’s hollowed-out pineapple and the stone tiki Squidward lives in.
Although the population of Bikini Bottom is uncertain, Stephen Hillenburg, the creator of the show, confirmed that Bikini Bottom is a large city. Before almost leaving the city, Sandy Cheeks sang a song about the city, describing it as 'crowded and smoggy' which are the characteristics of Los Angeles, although the physical look and feel of Bikini Bottom suggests that it is in fact a much smaller city. A one-time Pretty Patties joint created by SpongeBob attracted 46,853 customers. Almost everyone from the city is there, which may suggest a population of around 25,000 Bikini Bottomites. In the episode Squilliam Returns, Squidward mentions Bikini Bottom is a 'hick town', meaning it is probably quite small like most hick towns. On Krusty Towers, Squidward mentions Bikini Bottom is in the middle of scenic nowhere, which could mean it is very small, which is the criteria of isolated cities. On Nautical Novice, Mrs. Puff says "We're going to flatten millions of innocent lives!", which could mean that there are around 2 million people in Bikini Bottom. But in the episode What Ever Happened to SpongeBob, there is a sign that says 'Welcome to Bikini Bottom, Population: 538'.
Bikini Bottom is shown to be quite a clean city. Littering is highly prohibited, and the areas around Bikini Bottom are pristine. The only problem is that with high population and the amount of automobiles Bikini Bottom can become very smoggy, as mentioned by Sandy in The SpongeBob SquarePants Movie. Global warming has also affected Bikini Bottom, as seen in the educational short, "The Endless Summer." In "Industrial Park”, there are many toxic chemicals and pollution.
Bikini Bottom has a certain range of wildlife such as grass, seaweed, and coral making up most of the flora and some animals making up the fuana.
In Bikini Bottom, animals are similar to those "animals" in the real world.Some are treated as pets, while others live in the wild. A majority of "animals" live in the wild. First, Jellyfish are similar to bees. There are many different types of Jellyfish that live in Bikini Bottom. Pink are the most common, but they also come in green, blue, orange, yellow,and purple. In the episode The Secret Box SpongeBob states that Patrick may have the worlds only albino jellyfish. Jellyfish reside mainly in Jellyfish Fields, which has a population of four million Jellyfish. They make and live in hives, another similarity to real-world bees. In earlier episodes, jellyfish were plain pink. And later on, more jellyfish began to appear with spots, but plain pink ones still exist. Jellyfish are similar to cows in that they can be "milked" for their fresh jellyfish jelly. The jelly, which can be taken from the hive or from the actual jellyfish, is probably the Bikini Bottom version of honey (considering jellyfish are bees). Second, scallops are similar to birds. They are usually found in groups at Goo Lagoon, particularly acting as seagulls. Scallops are usually orange or purple. There is also a colossal clam named Clamu in Oyster Stadium. It's currently a mother of one. Also, the medium-sized variants of clams are shown to be similar to wolves (like in the episodes Texas, when they were seen howling, and The Thing, when Squidward was attacked by a clam in the truck) and the larger variants are likely to be similar to non-sentient whales (like Clamu). Third, sea slugs were seen in the video game, SpongeBob SquarePants: SuperSponge. They are known to dislike everyone. Fourth, seahorses, which are similar to horses, can be ridden and are very interested in food. SpongeBob kept a Seahorse in the episode, "My Pretty Seahorse" and named it "Mystery".
Fifth, the "Alaskan Bull Worm" is a large, omnivorous worm that attacked various parts of Bikini Bottom in its sleep in, "Sandy, SpongeBob, and the Worm". It eventually went on to destroy the entire city. Sixth, sea urchins, which are small "bug-like" creatures whose bites cause severe itchiness (a possible similarity to fire ants or mosquitoes). Seventh, Nematodes, which are worm-like creatures that travel in groups and consume common objects by eating or drinking them (a possible similarity to termites). They once destroyed SpongeBob's house by sucking the pineapple juice out of it and one time they almost destroyed the Krusty Krab. Eighth, rays , which are eagles . Other "animals" are treated as pets. Two well-known "pets" are snails and worms. Snails are similar to cats (because they "meow") and are common as pets, but they are also known to lurk in alleys and forests. A well-known character Gary the Snail is one of them. Worms are similar to dogs (because they bark) and these are also common as pets. At one point SpongeBob also owned a worm named Rex, an angry snail named Larry and a jellyfish.
- Main article: List of places in SpongeBob SquarePants
There are places and features outside Bikini Bottom. Most of them appear in video games.
Other towns and cities in SpongeBob SquarePants include Rock Bottom, Bass Vegas, Ukulele Bottom, Apple World, Atlantis, Leisure Village, Tentacle Acres, Palm Bay and Bottoms Up/Waverly Hills, New Kelp City, plus Bikini Atoll on the surface. Shell City (also on the surface) is six days away through a long and dangerous route beyond the County Line (the boundary of Bikini Bottom).