There and back again — Tolkien's 1911 walk, in relief

In the summer of 1911 a nineteen-year-old J.R.R. Tolkien walked through the Bernese Oberland and into the Valais. More than fifty years later he wrote that Bilbo's crossing of the Misty Mountains, "including the glissade down the slithering stones into the pine woods", was based on it (Letter 306).

This repository renders Switzerland's relief in R with rayshader and traces the walk across it. The interactive version, with the route drawn as you scroll, is at maciejkielar.com/work/tolkien-1911.

Pipeline

Step	File	Output
Country relief	R/01_switzerland.R	renders/switzerland_final_lakes.png (3500 × 3500, 350 samples)
Route-region relief	R/02_route_region.R	renders/route_region.png: Bernese Oberland and Upper Valais at ~52 m cells, matched to the country render's palette range and vertical exaggeration
Geometry	R/03_web_geometry.R	data/route_lv03.csv, data/border_lv03.csv: route and border projected to the Swiss LV03 grid the reliefs were rendered in
Web assets	tools/web_assets.py	web/relief.webp, web/relief-detail.webp (transparent, cast shadow kept; the detail colour-matched to the overview), web/route.json (coordinates the page draws with)
Preview	tools/preview.py	docs/route_preview.jpg, the image above

Rscript R/01_switzerland.R
Rscript R/02_route_region.R          # add `preview` for a quick framing check
Rscript R/03_web_geometry.R
python tools/web_assets.py renders/switzerland_final_lakes.png renders/route_region.png --out web   # --debug writes fit overlays
python tools/preview.py

Scripts download and cache their data in data-raw/ (or set RELIEF_DATA_DIR to an existing cache). Renders are slow: plan on tens of minutes for the full-size ones.

Both reliefs are rendered top-down (phi = 89, orthographic), so each image maps to LV03 with a plain scale and offset. web_assets.py fits the country render by matching the relief's bounding box to the border's (scales agree between axes to within 0.1%). The regional render's southern edge is snow on white paper, so its fit is refined by maximising the overlap between the projected border and the rendered relief.

The route

data/route.csv lists every point the line passes through, in order. Rows with stop = 1 are the stops shown on the page; each says how it is known:

• Letter 306 — Tolkien's own recollection (to his son Michael, 1967–68).
• Dated record — the Ober Steinberg guest book, 5 August 1911 (Scull & Hammond, The J.R.R. Tolkien Companion and Guide).
• Reconstruction — order and stages pieced together by later research; firm from Interlaken to Brig, looser beyond.
• Interpretation — links to the books (Lauterbrunnen as Rivendell, the rockfall as the stone-giants) proposed by readers and biographers such as John Garth.

Between stops the line follows valleys and passes through intermediate places. It is a reconstruction, not a recorded track.

Data

Elevation via elevatr (AWS Terrain Tiles) · border from GADM · rivers from HydroRIVERS · lakes from Natural Earth · lighting HDRI from Poly Haven. Downloaded data and full-size renders are not committed; each source keeps its own licence.

More reliefs: thecodeak/rayshader-reliefs.

Licence

Code: MIT.