Earth Sandwich / City antipodes / Haiphong

Antipode finder · Vietnam

The antipode of
Haiphong.

Draw a straight line from Haiphong (20.86° N, 106.68° E) through the centre of the Earth and it comes out at 20.86° S, 73.32° W, in the South Pacific Ocean, 323 km from the nearest dry land, off the coast of Chile. The other slice of an Earth sandwich would sink.

Two globes: one centred on Haiphong, one centred on its antipode at 20.86° S, 73.32° W
Above HaiphongAbove the antipode
Haiphong
20.86° N, 106.68° E · about 40 m above sea level · 2,625,200 people
Antipode
20.86° S, 73.32° W
What is there
The South Pacific Ocean; the sea floor there lies about 4,760 m below the surface
Nearest dry land
323 km from the antipode, on the coast of Chile
Nearest town
Iquique, Chile · 338 km from the antipode
Nearest big city
Arequipa · 531 km from the antipode
Sandwich verdict
SOGGY the other slice lands in open water
Nearest exact spot
324 km away, 31 km from Leizhou, China ⇄ 62 km from Alto Hospicio, Chile

Can you make an Earth sandwich from Haiphong?

No, not from Haiphong itself. The other slice would land in the South Pacific Ocean, 323 km from the nearest dry land (Chile), where the sea floor lies about 4,760 m below the surface. Boats do not count (Sandwich Law § 1.3).

The nearest place from which an exact Earth sandwich is possible is 324 km from Haiphong, 31 km from Leizhou, China. Its other slice would go down 62 km from Alto Hospicio, Chile.

How this was worked out: the antipode flips the latitude and moves the longitude by 180°. Land or sea comes from the OpenStreetMap coastline the map uses; the sandwich verdict and elevations come from the verifier's 0.2° grid (Natural Earth land, ETOPO 2022 relief); water names from Natural Earth; towns and populations from GeoNames. The city's position is GeoNames' point for it; a big city's suburbs spread tens of kilometres around that point, and the figures move with them. Generated 2026-09-29.