Meet halfway – a fair point for everyone

Where should friends from different towns meet? “Halfway” has more than one meaning once three or more people are involved. Cartograph shows the main answers side by side.

Open the example

File → New from template… → Meet halfway: Berlin, Hamburg, Munich. The Meet halfway tab shows a map with the three cities in blue, dashed lines to the orange fairest point, and a small black diamond for the least total distance.

Add and edit people

In People each row has a name and a place. To add someone:

1. type a Name,
2. type the Place (coordinates) – decimal degrees like 52.52, 13.405, degrees and minutes, UTM, MGRS or a plus code,
3. press Add person.

You can also click on the map to add a person there. Addresses are not looked up: Cartograph contacts no search service. The bin button removes a person. Up to twelve people are possible.

Read the meeting points

The table under Meeting points lists every candidate with its coordinates, each person’s distance and the Longest trip:

• Geodesic midpoint (two people only) – exactly half-way along the shortest line on the Earth’s surface.
• Fairest point – nobody travels further than necessary: the longest trip is as short as possible. For Berlin, Hamburg and Munich nobody travels more than about 306 km.
• Least total distance – the sum of all trips is smallest. It is often close to one person, which is efficient but not fair.
• Centre of gravity – the average position, for comparison.

All of these are straight-line distances on the WGS84 ellipsoid, not travel times.

Fair by road

With a map loaded, tick Also find the fairest place by road (uses the loaded map) under By road and choose the Travel mode. Cartograph computes walking or cycling distances from everyone along the streets of the extract and picks the street junction with the shortest longest trip. It appears in the table as Fairest by road and as a green triangle on the map. Everyone must be within 1 km of a road of the loaded map.

This works best inside one town; for people in different cities, use the straight-line answers.

Export and privacy

Download GeoJSON saves all points for other map tools; Download SVG saves the map. The places of the people are personal data: they stay in your browser and in your project files, and Share link… never includes them.

Next: the true size of countries.