UpToWhere
UpToWhere · Can you see it?

Can you see Mont Blanc from Lyon (Fourvière)?

Yes — you can

159 km line of sight toward the east (bearing 86°), computed on 30 m Copernicus terrain with Earth curvature and standard atmospheric refraction.

Lyonnais swear that on certain autumn evenings the white dome of Mont Blanc appears behind the city's rooftops, 160 km away. Skeptics call it a legend. The terrain has an answer.

3D terrain view from Lyon (Fourvière) toward Mont Blanc
Straight-line distance159 km
Direction86° east
Observer eye level295 m
Target elevation4,811 m
Curvature drop at the target1,716 m
Clearance margin+4 m

From Lyon (Fourvière), at an eye level of 295 m, the sightline to Mont Blanc runs 159 km and clears every ridge in between. Over that distance Earth's curvature drops the target 1,716 m below a flat-earth line — but at 4,811 m, it still rises above the horizon. The view is geometrically real: whether you actually get it depends on haze, not terrain. The tightest squeeze is mid-path, where the sightline passes just 4 m above the terrain at km 159.

The line on the map

Satellite map with the sightline from Lyon (Fourvière) to Mont Blanc drawn in red
The 159 km sightline over satellite imagery, drawn as the great-circle path light would follow.

The terrain profile

-0 m2,000 m4,000 m sightlineLyonMont Blanc 0 km159 km50100
Elevation profile from Lyon (Fourvière) to Mont Blanc. Like every elevation profile, the vertical axis is stretched (≈10× here) — but the geometry is real: mid-path, Earth's surface genuinely stands 493 m above the straight line between the two points. Light bends only slightly around that bulge, so whatever it covers stays hidden.
Check your own two points with the calculator →

Frequently asked questions

Can you see Mont Blanc from Lyon (Fourvière)?

Yes. The terrain-limited line of sight is clear across 159 km, accounting for Earth's curvature and standard atmospheric refraction. Atmospheric haze is the only thing that can hide the view.

How far is Mont Blanc from Lyon (Fourvière) in a straight line?

159 km great-circle distance, on a bearing of 86° (east).

How much does Earth's curvature hide over 159 km?

At the target's distance the curvature drop is about 1,716 m: anything lower than that (relative to the observer's horizon plane) is hidden behind the bulge of the Earth. Mont Blanc is tall enough to rise above it.

How was this calculated?

UpToWhere walks the full terrain profile between the two points on 30 m-resolution Copernicus GLO-30 elevation data, applying Earth curvature and standard atmospheric refraction (k = 0.13) — the same physics surveyors use. You can run the same point-to-point check between any two places on Earth.

More famous sightlines

Wondering about a different pair?

The free calculator shows how far you can see from any point on Earth. Pro adds point-to-point checks — this exact analysis, between any two places you choose.

Open the calculator