Wednesday, August 20, 2014

Search Challenge (8/20/14): The shortest--and flattest--route there.

Riding through the Santa Maria valley, CA. 

AS you've probably figured out by now, I love to go for long bike rides, especially in hilly terrain.  Mountains?  Bring 'em on.  Rolling hills?  Even better.  

But that doesn't mean I don't pay attention to the hills.  Every cyclist wants to have some idea about what's coming up, if only to be sure to have brought along enough water and food.  

A common thing for cyclists to do is to check the routes before heading out, just to see how hilly the day looks to be.  Or, more commonly, to choose a route that matches your abilities (and aspirations) for the day.  Some days, you want to attack the hills--other days, you need to rest a bit.  

That common question leads to two fairly simple route selection Challenges.  In both cases, there are two obvious routes from Point A to Point B.  The question is simple:  Which route is flatter?  (To be precise, find a route with the smallest elevation gain.)  

1.  Suppose I'm in the Southwest of the US and want to do a bike ride from Farmington, New Mexico, to Durango, Colorado.  What route would you recommend for the least overall elevation gain between the two cities?  
2.  Suppose that a few months later I'm in the Southeast of France and want to ride my bike from Echirolles (France) to Oulx (Italy). What route would you recommend for the least elevation gain between these two cities?  

The routes here are pretty obvious--when giving your answer, just say which roads you recommend. (For example, in NM/CO, do you recommend routes 140 and 170, or 550?  I don't need turn-by-turn routes, unless you find a REALLY unusual solution.)  

I'll give a hint tomorrow about how I solved these Challenges, but for today, I'll let you work on them.  (And we'll chat about why there are two versions of the same problem.)  

As usual, in addition to your solution, be sure to tell us your thinking--HOW did you solve the Challenge?  And what deadends did you explore along the way?  

For an unusual extra credit (and really optional):  Why is the route from (somewhere near) Echirolles to (somewhere near) Oulx of historical interest?  Who else would have deeply cared about finding the flattest path between these two locations?

Search on! 


  1. Being a long distance cyclist myself planning a route is something I do regularly. So I have used the tools I know. Using Strava in this case or a previous app I used to use is my go to solution. Now you wanted the least amount of elevation gains. Answering that is relatively easy if we just consider the numbers.

    Farmington to Durango -

    Option 1 - Route 550 is 858 m elevation gains and 86.6 kms - rolling hills with steady climbs.

    Option 2 - Route 170/140 is 1068 m elevation gains and 86.4 kms however the route is one long steady climb but then a nice downhill into Durango which is always nice at the end of a ride.

    My preference I believe would be Option 1 based on these facts. But if we are doing a return trip I would return using Option 2 - that would be a nice ride back.

    Echirolles France to Oulx Italy

    Option 1 - Route 1091 is 3654 m elevation gains and 140.9 kms with two steep climbs

    Option 2 - Route A41 & A43 is 3919 m elevation gains and 189 kms. one steep climb but the rest is relatively flat.

    At first I didn’t see these two routes as comparable until I look at the elevation graph. Option 2 has a lots of flat road with steeper climbing but the distance is much longer. Option 1 has lots of continuous climbing. I believe I would prefer Option 1 based on these facts largely due to distance.

    I will have a look not using a specialized app to see how else this challenge may be done. As well I will check out the historical interest you mentioned.

    1. Here’s the maps created in Strava showing maximum grades on climbs which is something I would consider. As well I included a couple of my own routes more as a comparison for me to see how tough these rides would be. Maximum grade from Farmington to Durango turns out to be quite reasonable. However the climbs in the French Alps would be almost unbearable. Mind you the descents would be fantastic.

      Google Maps does offer an elevation graph for cycling routes. It is somewhat limited because you can’t tell the grade of the climb which is important. I didn’t find Google Maps worked well on in the French Alps.

      Wikimapia is another map I had a look at more to see what historical places I might find. I would say that the Tour de France and the Giro d’Italia have made the Alpe d’Huez quite famous.

    2. Just found a video of Highwood Pass ride I did. Cool nice memories. The map is included in the shared page above. And here is a video from Grenoble to Torino Leg warmers & booties ride.

    3. And one more just to entice you guys to come ride with me. The Banff Gran Fondo with the added bonus of a grizzly & 3 cubs. Great ride.

    4. Lovely videos, Rosemary. Thanks. (It's tempting!)

      When you used Strava, did you use the free version, or the paid version, to compute the routes?

    5. I am glad you enjoyed the videos. The routes were created on the free version of Strava at their website.

  2. Good day, Dr. Russell, fellow SearchResearchers


    Some days ago, I read that Google Maps now shows more information about cycling routes.

    [cyclist route elevation Google maps]

    Google Maps Adds Elevation Profiles To Bike Routes To Help You Avoid Those Steep Hills "...Just look for a route on Google Maps, choose the biking directions and look for the new elevation profile. Besides the graphical representation of those hills you will have to climb, the new card also shows you the total number of feet you will have to climb on your route (and those joyous miles you get to just kick back and try not to die while you barrel down the hill on the other side).The only time you won’t see the new elevation profiles, it seems, is for routes that are essentially flat...."

    In Google Maps [Farmington, NM, USA to Durango, CO, USA] Bicycle, Route options

    In Google Maps [Échirolles, France to Oul TO, Italy] Cycling not available.

    Went to other sites that I found in query.

    [echirolles to Oulx historic route]

    [Echirolles Oulx History]

    Sauze d'Oulx, Wikipedia"...with the Treaty of Utrecht (1713) France gave it to the house of Savoy; in 1747 its territory was the seat of the Battle of Assietta between France and Savoy's Kingdom of Sardinia..."

    [Echirolles AROUND(3) Oulx]


    1. Suppose I'm in the Southwest of the US and want to do a bike ride from Farmington, New Mexico, to Durango, Colorado. What route would you recommend for the least overall elevation gain between the two cities?
    A: Route via W Aztec Blvd and Co Rd 213. Total time 4h 46 mins.

    2. Suppose that a few months later I'm in the Southeast of France and want to ride my bike from Echirolles (France) to Oulx (Italy). What route would you recommend for the least elevation gain between these two cities?

    NO Answer yet.

    1. [cycling routes elevation comparison]

      Comparing cycling routes
      Recording World's Bike Paths Together

      [traza ruta ciclismo elevacion]

      Dibuja Perfil de Ruta (Draw Road Profile) There you can draw your route in Google Maps. After that, you have more options to choose: Kind of route, follow roads, show locations and in the top of page you can see elevation, route profile, 3D and other options.

      In this site, created the route.

      Follow Top roads: Total distance 162.66 km. Max elevation 2868.11 m. Min height 209.78 m. Also shows gradient and slope.

      Follow Secondary roads: Total distance 131.86 km. Max height 2628.1 m. Min 236.45 m.

      Following not roads: 88.54 kms. Max Height 3003.63 m. Min height 230.64 m.

      Best Route

      For an unusual extra credit (and really optional): Why is the route from (somewhere near) Echirolles to (somewhere near) Oulx of historical interest? Who else would have deeply cared about finding the flattest path between these two locations?

      [Echirolles France historical interest]

      Échirolles Grenoble
      Route Napoleon, Google Maps

      [Oulx historical interest]

      No answer yet.

    2. I have learned some new things as I do each week while doing Dr. Russell's Challenges. Here are some of them

      [Alps historical events]

      Alps etymology
      Transhumance Wikipedia

    3. Thanks Ramón for the Etymology dictionary link. With the Transhumance article I believe there should be an addition to the list, Snowbirds. Canadians who winter/migrate to lower latitudes due to cold temperatures in search of warmth.:)

    4. Nice, nice, nice. I also didn't know about transhumance (human migration to follow the herds).

  3. Sometime ago, I noticed Google Maps has already done that job for us. Whenever Google Maps have the cycling option available, it will show you the elevation profile as well as the total gain (and loss).

    The first question has a simple answer on Google Maps, this way.

    For the second one, [ calculate elevation gain google maps ] was a good search string. I opened the first result (Sport Route Planner), whose snippet suggested to be what I wanted, but it seemed to be too impractical (apparently, you must enter by hand a vast array of points on your road). The second result, though, is the solution to our problem.

    On Google Maps elevation for a route, you enter the starting and destination points, just like on Google Maps. It takes a while to perform the calculations (with 8 thousand points found automatically on the way) but the results are clear.

    1. Farmington, NM to Durango, CO ↑ 1,588 ft via W Aztec Blvd and Co Rd 213
    2. Échirolles, France to Oulx, Turin, Italy ↑ 4,908 m via D1006 (found on Google Maps elevation for a route)

    1. Sorry for the lack of links. My fault: somehow, for the past weeks or months, my brain got stucked on a html instead of the proper a href and I keep repeating that error. :(

      Sport Route Planner
      second result = Google Maps elevation for a route, by Doogal = Chris Bell
      Farmington, NM to Durango, CO
      Échirolles, France to Oulx, Turin, Italy

  4. From my history lessons I remember that Hannibal (a Carthaginian military commander) led an army with elephants over the Alps in 218 BC to attack Rome. One of the most celebrated achievements of any military force in ancient warfare.
    There is a lot of controversy on the route he followed:'s_crossing_of_the_Alps

    A bike tour in the footsteps of Hannibal from Barcelona to Rome:

  5. PREVIEW failed this time. Comment count remains zero even with comments in

    Using Farmington and Durango calculates total ascent 2868 feet but this apparently does not use bridges to cross rivers qnd other deeps but rather uses Google's method of down and up so the total is close.

    Now, which route ?

    140/170 and 550 are similar distances with similar elevation gains of about 3000 feet. However the big difference is that the first 40 miles of the 140/170 is a steady ascent. 550 has a some ups and downs making for a more interesting and easier ride so appearing flatter.

    Echirolles to Oulx. Using same site it looks to be a tough ride by any route. A41/A43 ascent of 15,000 ft over 100 miles. First 40 miles looks not too bad climbs steadily first 40 miles then very steep for 50 miles.

    Two other routes had total ascents of 19,000 feet.

    I think Mr Hannibal and his heffalumps were the historical travellers 2200 years ago. No one knows his route for sure now.

    Another interesting Search

    jon tU

    1. After reading Hans and Jon tU posts did this search:

      [Hannibal Alps route Google Map]

      Hannibal Crosses the Alps :Cartographia Includes Minard's map

      Hannibal Crosses the Alps

      [Hannibal Alps route intext:echirolles intext:oulx]


      I'll try to find the query that brings the same answer you found, Jon and Hans. Great work!

      At the moment, no clue about how to get that answer searching.

    2. Following up on Han's recollections I found a book "A History of Rome" with a specific reference to the Grenoble to Turin route.

      Other ideas I have seen have to do with a cable car (flattest town in France), a train and a tunnel (Seven Mile Tunnel).

  6. I remember seeing recently that Google Maps added showing elevation for bike routes so began with
    [ google maps show elevation ]
    1. I chose 516 to 550 to some smaller roads and trails.,+NM/Durango,+CO/@36.9999697,-108.1680161,11z/data=!4m14!4m13!1m5!1m1!1s0x873b8f00ad0c7ec7:0xc823b1b63b534e1a!2m2!1d-108.2186856!2d36.7280583!1m5!1m1!1s0x873c02a6bd85fc23:0xdc2b8882a3a67e5a!2m2!1d-107.8800667!2d37.27528!3e1
    ↑ 1,588 ft· ↓354 ft

    The bike route only works in Google Maps in the US it appears.
    Searched [ bike route planner elevation ]
    Created this route.
    Max 6741.77 ft Min. 761.88 ft

  7. Fred - great map and graphs on Cycleroute. thanks. I can make personal use of that. In particular the ability to categorize climbs is great. Well done.