This follows on from more interesting new maps posted here.
I thought that So. Cal. Spanish missions were early (mid-18th c.)... well here's an earlier story of intrepid early diplomats & missionaries - not seasoned sailors as Longest tall ships routes here - after long-distance missionaries of the Apostolic Levant here. Perplexity opens here as:
The town of Coria del Río, located in Andalusia, Spain, is home to a uniquely historic community of descendants of Japanese samurai. This remarkable connection dates back to the early 17th century when a diplomatic expedition, known as the Keichō Embassy, was sent by the daimyo Date Masamune from Sendai, Japan. The embassy, led by Hasekura Tsunenaga, traveled to Spain via Mexico in 1613 with the aim of establishing diplomatic and trade relationships between Japan and Spain, as well as with the Vatican...
So how did they make it to the other side of the world then? Again from Perplexity here:
The ship sailed across the Pacific to New Spain (modern-day Mexico), arriving in Acapulco in early 1614 after about three months at sea. The delegation then traveled overland from Acapulco to Mexico City, spending some time there. From Veracruz, they boarded a Spanish fleet commanded by Don Antonio Oquendo, crossing the Caribbean and Atlantic to Spain. The fleet reached the port of Sanlúcar de Barrameda near Seville in early October 1614.
From Sanlúcar de Barrameda, the delegation traveled up the Guadalquivir River in two galleys to Coria del Río, a town near Seville, where they stayed for a time. Following this, Hasekura and his group proceeded on a land route through Seville, Madrid, and Barcelona to carry out their diplomatic and religious missions. This historic arrival in Coria del Río and subsequent travels marked the first major Japanese diplomatic mission to Europe...
Simply created this table here with the sea & overland travels above. I doubled these up (offsetting them one up & doubling the last one) to create begin & end intervals to create two route maps:
Geodesic (Great Circle) Line in light green below for air travel today:
- shortest distance between two points on a sphere or ellipsoid (Earth’s surface).
- the direction (bearing/azimuth) changes continuously along the route.
- used in aviation and intercontinental routes for minimum travel distance.
Rhumb (Loxodrome) Line in pink below for ship navigation then:
- constant bearing/azimuth: crosses all meridians at the same angle.
- not usually the shortest route between points (except along the equator or meridian).
- easier for navigation (traditional marine navigation) because you set your compass heading and keep it constant.
Thus is what it looks like in America-centric Equal Earth:
click to enlarge, full size here
The map below wouild have been more a-propos at the time however...
Mercator projection also:
- rhumb lines (lines of constant compass bearing) are straight lines on a Mercator chart. This means a sailor can plot a straight line between any two points and simply maintain a constant compass heading throughout the journey, greatly simplifying navigation.
- near the equator, distortion on the Mercator is minimal—shapes and distances are reasonably accurate for practical navigation.
- the projection is conformal (it preserves angles and shapes locally), so bearings and directions are shown correctly, which is crucial for setting and maintaining courses with a compass
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| click to enlarge, full size here |
Spilhaus albeit ocean-centric doesn't wark that great here:
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| click to enlarge, full size here |
And just for fun - wait until the end... - here is Polar Azimuthal Equidistant also for ocean continuity:
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| click to enlarge, full size here |
Now for the fun part 🥁 Flat Earthers rejoice! Antarctica does indeed circumvent our Earth, to stop us from falling over the edge into oblivion as below 😉
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| Perplexity AI generated image |




