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Find the flattest route between any two points in SF

73 points by ishan0102 ago | 20 comments

jez |next [-]

It would be neat if it there were an option which added distance and elevation gain, but minimized the grade.

For example, a route from SOMA to Nob Hill can be made flatter by approaching from either the east or west. Technically the "flattest" as measured by elevation gain between the two is straight up Taylor from Market, but it's much nicer to bike to the top of Nob Hill by going out of the way (e.g. Polk → California, Embarcadero → Broadway, etc.)

askjdfksdbfhk |next |previous [-]

There's a weird thing going on at 22nd and San Jose in the Mission, where it doesn't seem to understand that you can simply continue down 22nd, but instead takes a hook down San Jose before backtracking. I see some other weird discontinuities like this as I click around.

I have to say that the Claude UI has made many inexplicable decisions here, including (but not limited to) the mysterious color coding, the confusing continuous slider over a discrete set, and the weird positioning of the height labels in the altitude graph.

andalinmicphew |next |previous [-]

Checkout https://bikehopper.org for solid elevation, bike infrastructure and transit-aware routing around the Bay Area. Some friends and I built this about 5 years ago and continue to maintain it. We use 1m DTM elevation data for SF and 50m for rural areas. DTM is a must for elevation based routing in SF as there are so many sizable buildings, large trees the other models fail hard.

verst |root |parent [-]

Can you please consider expanding it to include Seattle? Or better yet Puget Sound area? 1m DTM elevation data is available here. We have many amazing bike trails, but also plenty of hills that must be avoided.

scaredginger |next |previous [-]

This is great. Since SF is mostly a grid, I used to use the heuristic of only choosing paths that wouldn't take me further from my destination, avoiding going downhill but choosing the shallower uphill climb if a choice is given.

Other than knowing the direction of my destination, it only used local information

danserfaty |next |previous [-]

It's not accurate. I mapped it from my house on Cabrillo St in the outer Richmond to 4th avenue and it says I need to climb 25th avenue then walk Geary instead of correctly telling me to use 23rd avenue that is completely flat.

jeffbee |root |parent |next [-]

I think this comes down to the DEM they are using. I think it would have come out better if they had used USGS 3DEP DTM at 25cm.

Edited: which apparently is hosted for free on AWS S3.

almstimplmntd |root |parent |previous [-]

ah, I think this is related to SF's "Slow Streets" program and a genuine bug in the parser.

Cabrillo is a Slow Street, and the parser read its "destination-only" tag as closed to pedestrians, so the tool couldn't see the street at all (and started you a block over?). fixed and deployed; your trip should now go Cabrillo → 23rd → Geary.

jazzyjackson |root |parent [-]

“genuine bug in the parser” -> red flag for slop for those keeping track at home

pokpokpok |next |previous [-]

The wiggle!

(in honor of my old commute, which I miss)

https://flattensf.com/#t~-122.40850~37.77493~-122.50940~37.7...

cheeaun |next |previous [-]

Cool, I used to build this https://github.com/cheeaun/steepless (2014)

jdxcode |next |previous [-]

someone should make flattendallas.com as a joke

mvkel |next |previous [-]

Absolutely love the live profile updating when you swipe from flatter to shorter.

Terr_ |next |previous [-]

> The slider runs along the whole trade-off between distance and climbing [...] Climbing is cumulative gain

Another mechanism might be a kind of user-defined cost-curve, where a gradual climb to 10 might be preferred over a steep climb to 8, etc.

jeffbee |root |parent [-]

You want OpenTripPlanner. Their triangle lets the user trade distance, climbing, and safe facilities.

https://github.com/opentripplanner/OpenTripPlanner

https://github.com/opentripplanner/OpenTripPlanner/blob/dev-...

qurren |next |previous [-]

Doesn't Google Maps in bicycle mode already do this?

Arainach |root |parent [-]

There are many constraints to satisfy, and avoiding hills is but one of them.

Most of us would take a hill with a protected bike lane over a flat 45mph.

tedd4u |next |previous [-]

Cool! Any way to toggle on street names on the map?

fnord77 |next |previous [-]

Try downtown to somewhere in Bernal, say Progressive Grounds coffee house.

The flattest route is only 0.2 miles longer than the shortest, but goes from 200ft of climbing to 500ft of climbing, 12% max grade to 22% max grade.

Apple maps picks the shortest every fucking time.

sergiotapia |previous [-]

This reminds me of a funny story for my first trip to SF. I left the office at 9 and had time to burn until my flight at 1pm.

I decided to walk to the japanese district and check out some shopping there, it was 15 minutes in google maps. I walk every day at home, 2 miles is like 30 minutes ish for me. For some reason it took me 50 minutes (!), and a WHOLE lotta climbing.

And I had to dodge a bunch of drug addicts yelling at people.

By the time I got to japantown I was drenched in sweat lmao so I had to cool off in the shade but man that SUCKED. Never again.