AI-ASSISTED · EDITOR-REVIEWED

Theme brief

A line can be a route, a boundary, a flow or the trace of something that changed over time. Use width, rhythm and direction carefully: a thick line reads as more important, while arrows and animation imply movement.

Official prompt
“A map challenge classic. Map with lines.”
30DayMapChallenge 2026

02

WAYS IN

Four map ideas

01
Trace one river from source to sea and annotate the places it changes character.
02
Compare a week of running or cycling tracks without revealing your home location.
03
Map night trains or ferry routes as a stripped-back network.
04
Show how a street grid changes across the edge of a city.

03

IN THE DIRECTORY

Recommended tools

QGIS

Offers line simplification, offsets, casing, arrows and distance-based styling.

Open source · View details

Mapbox

Useful for a responsive web map with line gradients and zoom-dependent styling.

Freemium · View details

uMap

A low-friction choice for drawing and sharing a small route map.

Open source · View details

Mapshaper

Cleans, simplifies and converts line datasets before you design the map.

Open source · View details

04

START WITH A CLEAR LICENSE

Data sources

OpenStreetMap roads, rail and paths

Regional extracts are safer for bulk work than public Overpass endpoints.

ODbL 1.0 · attribution required Natural Earth rivers and lake centerlines

Generalized physical lines suited to regional and world maps.

Public domain GTFS transit feeds

Routes, stops, schedules and sometimes real-time feeds; check each publisher.

Varies by transit agency

Licenses are a planning aid, not legal advice. Check the source record and version you actually download; terms can vary within a catalog.

05

BEFORE YOU EXPORT

Cartography check

Give the line hierarchy before adding labels: one visual treatment for the subject, a quieter one for context.

06

COMMUNITY MAPS

Selected work

Selections begin after this theme closes.

First participate officially by posting publicly with #30DayMapChallenge. You can then suggest that original post for our independent MapTools picks. We link to the source, credit every author and use images only with permission.

Suggest for MapTools picks