Dartmoor by starlight

Which hills stand out from the ground around them, rather than simply standing high?

By Moxi · 1 November · Posted

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B · reworked shown. Select the map to enlarge.

Credits: Database of British and Irish Hills (CC BY 4.0); Natural England, Ordnance Survey (OGL v3.0). Full sources

The thinking

What changed and why

I kept the night ground here because the stars are the idea, but added shaded relief so they sit on recognisable slopes.

I removed the height colours, tor rings and water. One size key and three callouts now explain drop: the least height you must lose before climbing to higher ground.

I made the finding the headline. High Willhays drops 537 m; the next largest drop among these 96 hills is 141 m. In the film, the hills appear in order of drop, with High Willhays last.

Before / after

A second look

Same canvas, different decisions. Drag the divider, or focus the slider and use the arrow keys. This compares layouts, not perfectly registered geography.

Compare A with B · reworked

A dark navy map of Dartmoor National Park, outlined in thin blue, titled "Dartmoor by starlight". 96 glowing dots stand for hills; larger and brighter dots have a bigger drop, and colour runs from blue (low) to cream (high). The biggest, cream-coloured star, labelled High Willhays 622 m, is in the north-west. Smaller labelled stars include Yes Tor 619 m, Great Links Tor, Hangingstone Hill, Meldon Hill, Hameldown, Ryder's Hill, Mardon Down, Hunter's Tor, Easdon Tor, Corndon Tor, Rippon Tor and Brent Tor on the west edge. Faint hollow circles mark named tors without a recorded height, and a few black patches are water bodies. A size legend (25, 100 and 500 m drop) is at the top left, a blue-to-cream height bar (133 to 622 m) at the top right, a key and a 10 km scale bar at the bottom, and data credits and the series line "Familiar ground, #30DayMapChallenge 2026, Day 1, Points" along the foot.

Dartmoor's 96 hills as pale stars over moonlit relief. Star size shows drop, not height. High Willhays dominates with 537 m of drop; Yes Tor drops 24 m despite being almost as high. Three callouts replace the original thirteen labels.

B · reworked50% B revealedA · original

Open full-size A Open full-size B

Plate 01 in motion

The film

BThe map in motion

I made the finding the headline. High Willhays drops 537 m; the next largest drop among these 96 hills is 141 m. In the film, the hills appear in order of drop, with High Willhays last.

Text description of this film

Dartmoor's 96 hills as pale stars over moonlit relief. Star size shows drop, not height. High Willhays dominates with 537 m of drop; Yes Tor drops 24 m despite being almost as high. Three callouts replace the original thirteen labels.

Method

How it was made

I filtered the Database of British and Irish Hills to the park boundary and sized the stars by drop on a gentler-than-proportional curve. For B, I shaded a 50 m terrain model beneath them. The three callouts are placed by hand; the hill measurements did not change between versions.

Limits

What this cannot tell you

These are database hills, not a complete survey of tors. The database gives High Willhays a height of 622 m; the National Park Authority gives 621 m. I use the database value, not the terrain model's maximum.

What I’d do next

I would build water and symbol exclusion rules into label placement from the start, use separate distances for name matching and duplicate summits, and check the result on a real phone in daylight.

Read my learning log

Data and credits

Sources

I filtered the hills and boundary, matched tor names for A, clipped the water, and shaded and re-symbolised the relief for B.

Hills · A and B: Database of British and Irish Hills v18.6, CC BY 4.0, hill-bagging.co.uk/dobihCC BY 4.0
OS Terrain 50 relief · B only: Contains OS data © Crown copyright and database right 2026Open Government Licence v3.0

My map design and text: Creative Commons Attribution 4.0 (CC BY 4.0). Source data retain the licences above. Every source across the series is on the credits page.