Eclipse August 12, 2026 · Castilla y León / Madrid, Spain
Will mountains block your eclipse view from Sierra de Gredos?
Gredos rises to 2,592 m at Almanzor — high enough to delay sunset by 5–10 minutes for valleys facing southwest. The path of totality just grazes this region; check terrain before committing.
The August 12, 2026 total solar eclipse over Sierra de Gredos happens at very low sun altitude — under 10° in many places. At that altitude, even modest hills or ridges in your western horizon can block the sun completely. Every vantage point below has been pre-checked: we ray-cast the real terrain horizon from its exact coordinate and report whether the eclipsed sun clears the ridge line, with a link to the live 3D simulation to verify your own spot.
Each verdict is computed by ray-casting 360° from the exact coordinate over free AWS Terrarium elevation data (30 km range) — the same engine as the live 3D sky view. Margins under ~1° are flagged marginal: elevation pixels are roughly 110 m wide at Spanish latitudes and can miss sharp ridge lines, and trees or buildings are not included.
Ranked list: the best terrain-verified spots to watch the 2026 eclipse in Sierra de Gredos — clearance margins, totality durations and clear-sky odds, in order.
Key viewpoints
Hoyos del Espino Clear view at maximum
40.353°N, -5.171°W
The sun clears the terrain by 6.9° at the critical moment. Terrain hides the sun at 21:11 — before the partial phase ends at 21:25.
Check terrain in 3D →Navarredonda de Gredos Clear view at maximum
40.359°N, -5.130°W
The sun clears the terrain by 7.0° at the critical moment. Terrain hides the sun at 21:12 — before the partial phase ends at 21:25.
Check terrain in 3D →Arenas de San Pedro Blocked by terrain
40.211°N, -5.087°W
The terrain rises 0.6° above the sun — the eclipse is hidden behind the ridge from this spot. Terrain hides the sun at 20:32 — before the partial phase ends at 21:25.
Check terrain in 3D →Plataforma de Gredos Blocked by terrain
40.297°N, -5.276°W
The terrain rises 20.8° above the sun — the eclipse is hidden behind the ridge from this spot. Terrain hides the sun at 19:36 — before the partial phase ends at 21:25.
Check terrain in 3D →The night after: Perseids under a new moon
The eclipse is only half the show. The Perseid meteor shower peaks on the night of August 12–13, 2026 — and because a total solar eclipse can only happen at new moon, that peak night is completely moonless. It is the textbook-ideal Perseid year: up to ~100 meteors per hour under a genuinely dark sky.
The viewpoints above are already far from city lights, so stay after sunset. The radiant in Perseus rises in the northeast during the evening and climbs all night — rates improve after midnight into the early hours of August 13. No equipment needed: face the darkest part of your sky and give your eyes 20 minutes to adapt.
Plan the night sky at this spot →Drop a pin anywhere — Heliora computes the terrain horizon from that exact point and shows whether the eclipsed sun is visible above it.
Why does terrain matter so much?
- How low will the sun be during the eclipse?
- Across most of Spain the sun will be between 4° and 12° above the horizon at maximum eclipse. At 4°, a 100 m ridge half a kilometre away blocks the sun. At 8°, the same ridge needs to be 1.4 km away to clear it.
- How does Heliora know the actual horizon from my spot?
- Heliora downloads free AWS Terrarium elevation tiles around your pin and ray-casts 360° outward, sampling elevation every degree of azimuth and computing the apparent angle of the highest point. The result is the real local horizon from your exact GPS coordinate, not the flat-earth horizon.
- Does this work for buildings too?
- Not yet. Every verdict here is bare-earth: elevation data models the ground surface, not the buildings or trees standing on it. In a city — Bilbao, Santander, Madrid — a nearby block can hide a low sun that the terrain check says is clear, so treat an urban verdict as optimistic and check the sight line on the ground. Out on the ridges and viewpoints listed above, where these spots are, the ground is the horizon.
- Why did you build this?
- Generic eclipse tools tell you the sun's altitude but not whether your real horizon clears it. For a low-altitude eclipse like 2026-08-12 in Spain, that distinction is the difference between seeing totality and seeing nothing at all from a mountain valley.