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pool topology


i like swimming a lot; so when choosing a hotel, the pool is a pretty significant factor for me. how big is it? is it indoors or outdoors? how deep is it? what is its shape?

pool topology is the single most important factor when designing a pool.


basically, pool topology is how many holes a pool has. a hole is any area of land that is entirely surrounded by the pool; i.e. it has islands. a pool with an inauspicious amount of islands will always be subpar. for the sake of simplicity, we will ignore spas and other such subsidiary pools, and only focus on the main pool. i am also excluding other pool-like structures, like wave pools, and lazy rivers.

potato pool

the most common type of pool is the potato pool. it is seen often in aquatic centres and smaller hotels. like a potato, it has no holes. in my opinion, this is a terrible pool design. let me explain.

an illustration of a pool with no holes.

the pool pictured above is boring because it does not offer anything to the swimmer other than a pit filled with water. from any given point in the pool, you can see all other points in the pool (not accounting for refraction or murkiness). this does not motivate the swimmer to actually swim. there is no sense of discovery or adventure, as anyone can see the entire pool from where they are. why swim at all?

the lack of bridge support is a huge disadvantage for the potato pool. i'll go into more detail about this later.

donut pool

the next pool is known as the donut pool. like a regular donut, it has one "hole" in the middle.

an illustration of a pool with one hole.

this pool has a huge advantage over the common potato pool. that is, it is impossible to see the entire area of the pool from a single spot. this is better for a number of reasons, mainly that it inspires the swimmer to see the rest of the pool and swim.

another good thing about the donut pool is that you can use its shape to separate yourself from undesirable aquatic enthusiasts, like loud people, or people who sit on top of those little water jets doing obviously evil things. we can do better though.

double-donut pool

the double-donut pool has two holes instead of one. i couldn't think of a food with two holes in it.

an illustration of a pool with two holes.

this pool is better than the donut pool for obvious reasons. one, it obscures more of the pool from the swimmer's line of sight, giving them more to explore. it also gives more areas to hide from pool-weirdos. a pool like this also creates a fun zone in the middle i like to call the crotch.

exotic pool shapes

an illustration of two pools side by side. the one on the left has three holes, while the one on the right has four.

sometimes pools have more than two holes, although this is rare; the highest hole count i have seen in a pool is three. any higher, and you risk exhausting the swimmer, leaving them with too much to take in on a single swim, and risk having them get lost in the pool. also, having more holes can promote a sense of division among the loungers and sunbathers who occupy the islands within, which can poison the overall vibe of the pool environment.

getting around the lack of holes

sometimes, you just can't have a hole in your pool. it may be too expensive, or impractical, or even impossible on a given terrain. but that's okay, there are still ways to build a better pool.

remember, creating a good pool experience is all about blocking line of sight; if the swimmer can see everything, there is no incentive to explore. thus, a common pool shape for those in this situation is the humble bean pool.

an illustration of a pool in the shape of a bean.

while it can't achieve the greatness of the double-donut pool, it still manages to block line of sight from one side to the other, which is great for creating a fun pool experience.

pool size

the size of a pool is another important factor in its overall wonder level. however, you cannot simply just make a huge pool; you must first consider its topology. a potato pool, with no holes, can get boring or even intimidating if the pool is too large.

inversely, a donut or double-donut pool can benefit greatly from an increased size, as the pool will stay interesting and unintimidating due to its lack of lines of sight, as well as the increased size allowing swimmers to move a greater distance from potential water-based annoyances.

other pool-enhancing features


waterfalls are pretty nice. they increase the wonder level of a pool a lot, and depending on the design, can provide a place to sit while remaining pool-ready.


bridges are probably the best way to enhance a pool with at least one hole. they allow non-swimmers to safely pass over the water to align themselves parallel to a deckchair while their family or friends are having a good time in the pool. they can also create a cool experience for swimmers; chilling underneath a bridge in a pool is one of my favourite water-related pastimes.

pool-side bars

a bar inside a pool is probably the height of luxury for me. while i don't drink, being able to sit while in the water is an incredible experience.


  • the entirety of a pool should not be visible from any one point in the pool.
  • pools should have at least one hole to be adequately stimulating for swimmers.
  • pools probably shouldn't have more than three holes though.
  • the more holes a pool has, the larger it can be.
  • bean pools are a great way to create a great, hole-less pool experience.
  • there are ways to enhance a pool other than adding holes.