Find The Flattest Route Between Any Two Points In SF

TL;DR

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Flatten SF is an interactive route planner that lets users compare paths between San Francisco locations by distance and cumulative climbing. Its creator says routes are calculated in the browser from more than 160,000 street segments and elevation data; the source material does not give a release date or independent accuracy assessment.

Flatten SF, a browser-based route planner credited to Drew Edwards, lets users compare routes between San Francisco locations by distance and cumulative climbing. The tool displays options along a distance-versus-elevation trade-off, giving walkers and cyclists a way to look for routes with less uphill gain rather than relying only on the shortest path.

The site says it calculates routes in the browser across more than 160,000 street segments, using elevation from USGS 1-meter lidar and a street network drawing on Overture and OpenStreetMap data. Users enter starting and ending points and move a slider between the shortest route and routes that trade extra distance for less climbing. The page says place search works offline because San Francisco intersections, places and addresses are built into it.

Flatten SF describes the slider as covering routes that are not beaten by another route on both distance and climbing. Moving it toward flatter options never shortens the route or adds climbing, according to the site. Climbing means cumulative elevation gain along the route, not simply the elevation difference between its endpoints; a route can climb and descend even when it starts and finishes at similar heights.

The page distinguishes travel modes: stairways are allowed for walking and excluded for biking. It also shows faint lines for other routes along the distance-and-climbing trade-off. The source material does not provide example journeys, route measurements, or a separate evaluation of how closely the results match conditions on the ground.

Choosing Between Distance and Climbing

San Francisco’s steep streets can make two routes of similar length feel quite different. By putting distance and cumulative climbing on the same control, Flatten SF makes that trade-off visible for people who want to avoid uphill effort, compare walking options, or plan a bike trip without stairways.

The tool’s value depends on what a traveler prioritizes. A flatter route may add distance, while the shortest route may involve more climbing. Showing a set of alternatives gives users a way to choose according to their needs instead of treating one route as best for everyone. The page describes how it calculates and presents options, but does not claim measured health, accessibility, or travel-time benefits.

Street Data and Elevation Inputs

Flatten SF combines a street graph with elevation measurements to estimate how routes rise and fall. Its description names USGS 1-meter lidar as the elevation source and Overture and OpenStreetMap as sources for the street network. It says computation happens in the user’s browser and that local place search is built into the page.

Those details explain the tool’s approach, but the supplied report does not document when it launched, how frequently the street graph is updated, or the methods used to validate elevation and route access. It credits Drew Edwards and points readers to source data and a full analysis, but those materials were not included in the source text provided here.

“Routes are computed in your browser over 160,000 street segments, using USGS 1 m lidar elevation and the Overture / OpenStreetMap street graph.”

— Flatten SF

Route Accuracy and Data Updates

The source description does not say when the page launched, how often its street and elevation data are refreshed, or how route accuracy has been checked. It also does not explain how the tool handles temporary closures, private access, construction, or other conditions that may affect whether a mapped street segment can be used.

No specific route examples or independent test results are provided in the supplied material. Users therefore have the tool’s stated data sources and routing rules, but not published evidence here about how its suggested climbing compares with a trip in current street conditions.

Further Analysis and Route Checks

Flatten SF points users to its source, data and full analysis for more detail. The supplied description does not announce a scheduled update, new feature, or other next milestone. Any further assessment would need to establish how current the underlying street and elevation data are and compare selected routes with conditions on the ground.

Key Questions

What does Flatten SF do?

It compares routes between San Francisco locations by distance and cumulative climbing, letting users move between the shortest option and flatter alternatives.

What data does the route planner use?

The page says it uses USGS 1-meter lidar elevation and a street graph based on Overture and OpenStreetMap, covering more than 160,000 street segments.

Does the climbing figure mean the difference in elevation between the start and end?

No. Flatten SF says climbing is cumulative gain along the route, so it counts uphill sections rather than only the net elevation change between endpoints.

How does it treat stairs?

According to the page, walking routes may use stairways, while bike routes exclude them.

How current and accurate are the routes?

The supplied description does not state when the data were last updated or provide independent accuracy results. It also does not describe how temporary street conditions are handled.

Source: hn