It’s the long weekend and you have a fun car, a full tank of gas, and a good set of tires. It’s time to have fun, but where do you go? Of course, you can always wing it and see where the road takes you. Me personally? I want to make sure I get to get to my destination before dark, so if the goal is to find the best driving roads, and especially if I’m cut for time, I’m going to want to plan. Luckily, there is a website to help me find those twisties.
Curvature, whose tag line is “Find Twisty Roads,” is an open-source web application that uses data mapping to finding the curviest roads in the world, with the company saying:
Curvature helps those who enjoy twisty roads (such as motorcycle or driving enthusiasts) find promising roads that may not be well known. It works by looking at the geometry of every road segment and adding up how much length of the road is sharp corners, broad sweeping curves, and straight areas. The most twisty segments can then be viewed on the web or downloaded as KML map files that can be viewed in Google Earth.
To pull this off, Curvature relies on OpenStreetMap, commonly referred to as OSM. As the site suggests, it’s basically like contributing to a Wikipedia page; users can add details to the maps like road type, road surface, geographical markings, elevation changes, and traffic signs. This helps Curvature identify where the twistiest ones are.
When you open up Curvature, it looks like a bunch of psychedelic spaghetti. Refer to the legend though, and it all becomes quite clear. It’s yellow for least twisty, pink for the most, red in the middle.
The intention behind the program apparently comes from the heart. The founder, Adam Franco, a software developer, created Curvature as a passion project in 2012. As the company’s site notes, Franco built Curvature because he loves to lean into the turns:
Historically, our navigation tools like highway maps and GPS routing algorithms strive to help people get efficiently from one place to another, and in doing so place an emphasis on the “fastest route”, with the biggest roads and highest speeds. While these are often useful metrics, what they don’t capture easily and certainly don’t highlight is how fun a road might be to ride or drive. I wrote Curvature to builds maps that highlight how fun a road might be — where fun is defined as lots of time spent leaning into curves.
To demonstrate how it works, I’ll refer to his example of a route through the Adirondack mountains near where he lives in Connecticut:
As you can see, he uses Google Maps, which is full of bright details that are initially difficult to see. The lines that are visible to the naked eye in separate shades of yellow. The lighter the color, the less it is used as a main road. And then of course, the green and blue patches to indicate land changes and water channels.
Now let’s set a destination:
Okay, so it looks like Adam’s goal is reach Saranac Lake, NY some two hours away. Now the question is whether there are some great twisty roads for him to enjoy. To do that, we’ll pull up a Curvature map of the same area. This time with information fed from OSM into Curvature to see what comes up:
It looks like Adam is in for quite the adventure! At least three times on the route, he’ll encounter brief stretches where the road curves to a sizable degree, highlighted in red. Adam writes about the map we see above:
Pulling up the area in the area in the Curvature map, I can see that there a few smaller roads that are fabulously twisty and happen to generally parallel the most direct route. Curvature highlights the most twisty roads in a color-spectrum from yellow (moderately twisty) to pink (super twisty).
Note that the heavier, solid roads are ones that Curvature assumes are paved either because they have explicit surface tags entered in Open Street Map indicating they are paved, or are “primary” or “secondary” roads —which in most of the US and Europe are virtually always paved. The translucent roads are tertiary and smaller roads with no surface tags specified in Open Street Map yet.
You can see above that, when you click on a road, you get information about the surface, the length, and the curvature, with the latter being the important bit:
Now Let’s Try It For Ourselves
I live in Dallas-Fort Worth, TX near the airport. So even though I own a Miata, a 2021 MX-5 RF, finding time to break away is a challenge because I live in between the two cities — difficult but not impossible.
So I pull up the surrounding area, and voila:
Good news! There are a lot of colorful squiggles near me. A lot of them are orange to show decent curves if I feel like going for a leisure outing. But there’s one red line in the upper right corner that’s appealing. F.M. 455 that ends near McKinney, TX. The hilarious thing is I’ve actually been there and it is, indeed, a fun route to take. It’s been a while, I should go back.
Looking At David’s Hero Van Route
Soon, our very own David Tracy will fly out to St. Louis to rescue a $500 Toyota Sienna. Armed with tools and spare parts, he will attempt to coax life into it before setting off on a thousand-mile trek to Virginia before reaching his final destination in Chapel Hill, NC, where he will hand the keys to Jason to serve as his de-stressed hero van (all of his other cars are junk, and David fears this played into his recent heart troubles). Assuming David gets the van running, let’s explore what will come up on David’s journey.
As a quick reminder, here’s an outline of the route he plans to take:
Now, let’s pull up the Curvature results of the same area:
Okay, this bodes positive. I can tell he’s going to cross the Blue Ridge Mountains, but also some of the Appalachians and the surrounding Piedmont. Having lived in upstate New York previously, I know the east coast particularly well in terms of scenic beauty. That will be a pleasant drive to tackle.
You get the gist: All of us who write for this marvelous site keep a favorite driving destination in mind. For me, it’s north DFW country. For Matt Hardigee, it’s Blauvelt State Park hidden back upstate. For Thomas Hundal, it’s Rattlesnake Point where the old hillclimb course lies. We know how to have a great time.
Curvature isn’t perfect, with some rather flat roads appearing pink and some great roads seemingly not getting as much love as they deserve, but the idea behind the site is legitimately cool, and I implore our resident Wrencher of Rust Buckets to use Curvature and send pictures of the routes he takes along the way in that old van. God speed, David!
[Ed Note: Finding twisty roads will be the least of my concerns! It’s going to be like, one degree Fahrenheit in St. Louis, and I’ll be freezing my butt off trying to fix this van! -DT]
Image Credits: (Top graphic) Mazda; Stock.Adobe.com; (Story images) Curvature, author, David Tracy, Google Maps
Is this US only? Or the rest of the world as well?
Global
FM455 was nicer before the city all started moving that way, we used to have a company warehouse out there.
I’ve seen a few attempts at this, and this is definitely the best.
Google Maps is a fantastic tool. And an infuriating tool.
For a planned drive, use Google Maps website to plan a route. Then drag and drop the route over to roads that do not go through cities until you get the most interesting route within your time limits. You can download that map to your smartphone but it will eliminate all the twisty bits unless you have created them as waypoints (dropped a pin). So I often resort to printing (yes PRINTING) turn-by-turn instructions with the major turns highlighted because I am busy driving.
For an impromptu drive in the car, on the Google Maps app, enter your destination, choose the Avoid Highways option, and then look ahead on the map display for interesting road and take them. You will find some amazing roads (sometimes dirt or gravel!) and places. Maps will reroute so you don’t get lost and update the ETA so you don’t arrive late. When you get tired, just start following Google to your destination.
Awesome resource. Now I have more possibilities for where to take both the Triumph GT6 EV and the electric velomobile when they are ready. Both of these vehicles are made for going fast through curves.
Good but definitely not perfect. A lot of roads I used to drive that were both 55 mph and curvy didn’t show up. Most of those were main roads in a hilly area so they couldn’t help but have elevation changes and lots of curves. Also it marked private roads around me with speed humps and guaranteed lots of folks seeking medical attention or lots of trucks.
Just downloaded the kmz data for my area (North Carolina) and opened it in Google Earth. This is so rad. It accurately identifies all my favorite roads and has identified some nearby gems I missed.
Interesting. I have gone through the gambit of motorcycle twisty road apps. Rever, Calimoto, Detech. They did the job with varying degrees of success, but this might be a good free option for planning.
I just keep my eyes out for the big cautionary signs that warn “GPS routing not advised. RVs & tractor trailers prohibited “ as I’m driving for work. Drop a pin, then look more closely in maps later. Being in the Blue Ridge Mountains, there are plenty of targets 🙂
If you happen to be on 77 going through SW Virginia, try taking a side trip to/through Burke’s Garden, a collapsed limestone dome: the approach & departure are well worth the time. The northern border of Virginia once west of the Shenandoah Valley is a twisty playground as well—but early weekend visits are advised to avoid better avoid farm machinery. The Blue Ridge Parkway is well known, but many of the access roads less so. I highly recommend Rt 43 from Bearwallow Gap down to Buchannon. That’s what sold me on my Roadster during a weekend test ride: tight, steeply dished curves strung together. And, if you like gravel, there are plenty of playgrounds off the BRP as well—just watch for day hikers!
If you have a dual sport, gas up in Wytheville and ride up and over Big Walker Mountain. Then go into Burke’s Garden the back way, which is all gravel. I did it on my Triumph Scrambler so you don’t need anything too gnarly if you know what you’re doing. You can then leave on some pretty decent (twisty) pavement.
https://maps.app.goo.gl/mvjkMCajMbdUYgk58
If you want to make a day of it, leave Burke’s Garden and got to Tazewell (TAZ-wuhl) to catch the Back of the Dragon back to Marion/81.
I am convinced this area of the world has some of the best riding. And I’ve lived in SoCal and Denver.
Also – fun fact: The Vanderbilts initially chose Burke’s Garden for The Biltmore, but folks wouldn’t sell.
Did not know that!
I live some 2&1/2 hours east of that, and can attest to the little-known wonderful roads. 61 from Rocky Gap to Narrows on 460 is a delightful afternoon cruise—you’re alongside a winding creek the whole way. Don’t plan on 10/10ths, though: it’s more for just cruising. From there, you dip up into WV through Rich Patch and pick your poison by how jagged it is on Maps. I particularly recommend a picnic lunch at the glassed-in shelter at Hanging Rock Raptor Observatory. Mile & 1/2 (somewhat steep at first) hike, then you’re perched on jutting rocks and have miles of views.
Note that I first explored these in a Subaru with 6+ inches of clearance: I’m much more selective in the lowered Roadster—but can access those I mentioned in it. Hope I see y’all 🙂
Pure Genius. And no, I don’t mean David. 😉
BC Canada is literally just brilliant roads. Due to the topography, it’s the only thing we can build
This looks cool as hell. My general rule is numbered highways that aren’t interstates or generally called “Highway.” If it’s named, it’s almost certainly too close to the city or town.
These rules soften as you get more rural though: there are some amazing named roads that go on for miles and miles. Younger Mech (very irresponsibly) fancied himself a rally driver on a fair few of those roads. If you ever end up west of Asheville but not quite to Tennessee, though, oh man. You’ll get where you’re going feeling like you should be assigned a stage time without even trying.
Also, I will never believe that St. Louis is north of me. That’s just Big Cartography trying to sell maps, I know it!
I also look for ‘old’ in the name. Found Old Waitville Rd one night scrolling through Maps. Near Zenith and Gap Mills WV (some great food in Gap Mills: hit the Pie Shop!) WV. Basically 1 lane with gravel shoulders for passing. Not for seriously lowered cars or faint of heart. WV is full of roads I won’t take the Roadster on—but are damned fun in the shabby wrx. The earlier you get into them, the more fun you’ll have—and mountain sunrises are literally awesome.
A good rule is anywhere people go for whitewater is a good place to go drive.
And the longest one in my state is about 10km, has 7 red lights, and a speed limit of 35mph for a lot of it. And people wonder why I go away most weekends.
“our resident Wrencher of Rust Buckets”
Made me do a double take, for a second I thought I was being called out.
A lot of the colored roads in my area are dirt logging roads. And some of the great paved roads aren’t colored at all.
There used to be a great curvy road that I could drive on my way home. It wasn’t the most direct route, but it was fun to ride my GL1000 on it, and it was always light traffic.
Then the city widened it from 2 lane to 5. Took out all the tight curves. Now it’s pretty heavy traffic, and the nice little park with a playground in the middle is almost always deserted…
I don’t quite get it. Sounds like Curvature doesn’t come up with directions. So you have to make your own itinerary like a filthy animal?
*Zooms out*
Wow… so the middle part of North America is really boring isn’t it?
The idea is not new, multiple apps exist (Calimoto comes to mind) with the same approach, all/most of them driven by OSM data.
PS Your regular reminder to contribute to OSM if you want to improve routing/navigation/points of interest in most maps that aren’t Apple or Google. And you can’t get this sort of data analysis from Apple/Google either
DT needs an app that will find a warm loaner garage near St. Louis for wrenching.
I live in Central WI most of the year, and shit is DIRE here due to all the farmland and unimaginative idiots who layed out the roads (DO YOU LIKE STRAIGHT? HOW ABOUT TOTALLY STRAIGHT!!!) but these apps never show the hidden gems I know about. They’re cool ideas, but …. for much of the midwest, completely pointless. The curvy roads don’t show up, like all 3 of them.
I love this idea. Now I can plan my road trips and have fun the whole time
Great, this is just like having another fantastic fishing hole ruined by too many loose lips.
Where’s your sense of adventure people?
Go find your own without your phone.
Good news then. When I looked for the area near me, it missed 90% of the good roads around the Niagara Escarpment. Picked up Forks of the Credit…but everyone knows that. I suspect accuracy might be similar elsewhere.
Some good zigs and zags around there! Especially going up or down. Just don’t do those with a load of wine tourers. The Boston Hills also has some windy roads.
motorcycleroads.com is an excellent resource, I’ve planned a ton of great trips just looking up the 10 best roads in a state and stringing together as many as I can. Curated rather than based on general analysis like this app, good to use both
Finally! Technology put to it’s proper use!
“Finally! Technology put to it’s proper use!”
Why, cyberstalking, bullying and porn not good enough for you?