What Is the Roundest Lake?

(Last Updated On: April 27, 2022)

Alright most kids are probably guilty of this. That might include you, but it was probably when you were still around the age of learning to use crayons. Anyway, when prompted to draw a lake you might have just drawn a nondescript blue circle and called it a day. Which is totally adequate until you go see a lake in real life and wonder what the heck you were thinking. But maybe someone made fun of you for it and you want to feel vindicated. Super petty, but we respect it and have you covered. What is the roundest lake?

Further Reading: What Are the Largest Lakes in the World?

Round Lake

If you go to Seminole County in Florida, you’ll find a small private lake. It’s 12 acres and called Round Lake. For those looking for the roundest lake you might be getting a bit excited, because it means your search for the roundest, most circular lake is already coming to an end before it really had to start.

Unfortunately, Round Lake in Seminole County is not actually a circle. Or anything close to it. You can judge for yourself. In fact, we’re so annoyed about it that we’re going to start calculating the circularity of these lakes.

Math lesson time. Circularity (C) is what it sounds like, it’s a measure of how close to a perfect circle something is. A circle has a circularity value of C = 1. For reference, something like an equilateral triangle has a circularity value of C = 0.61 and a square is C = 0.79. The formula for circularity is given by C = 4*pi*A/P^2. A is the circle’s area and P is the circle’s perimeter. 

So Round Lake. The estimated perimeter is about 848 meters, which we got using this nifty map-based calculator here. Mostly because we’re not flying to Florida. The area of Round Lake is 13 acres, which is 52,609.1 square meters. Plug that into the formula and it turns out it’s 0.98.

There’s more than one Round Lake

There’s more than one Round Lake. There are actually more than 100 in the United States alone. 36 are in Minnesota and informally refers to another 80 in Michigan. There are another three in South Dakota, four in New York, two in Washington, one in Idaho, one in Arkansas, and one in Montana. There’s even a Big Round Lake in Wisconsin.

None of them are as round as the roundest lake, so we’re not even going to talk about them. 

Lake DeFuniak and Kingsley Lake

There are two naturally occurring lakes that are considered almost perfectly circular. In fact, they’re considered so circular that their perimeter is given in terms of circumference. 

Lake DeFuniak is a little less circular than Kingsley Lake, but both are in Florida. The former is in Walton County, and has a surface area of 38.6 acres.

Next is Kingsley Lake, which is 2,000 acres and located in Clay County. Some allege that Kingsley Lake is the oldest and highest elevation lake in Florida. At its deepest point Kingsley Lake holds a sinkhole, which is probably why it’s almost a perfect circle, and why it has the nickname “silver dollar lake.” 

Kingsley Lake

Speaking of lakes see if you know which ones are the biggest here.



About Kyler 705 Articles
Kyler is a content writer at Sporcle living in Seattle, and is currently studying at the University of Washington School of Law. He's been writing for Sporcle since 2019; sometimes the blog is an excellent platform to answer random personal questions he has about the world. Most of his free time is spent drinking black coffee like water.