20 Clever Ways People Navigated The World Without Maps Or GPS

The North Atlantic Ocean was often shrouded in fog during the Viking Age, leaving sailors in the dark for days without a glimpse of the sun. Icelandic sagas mention a “sunstone,” which could have been a calcite crystal, that splits light into two separate beams. By rotating the stone until both beams appear equally bright, the sailor can determine the sun’s location. The math of optics suggests it would work, but we have no confirmed example of one in a Viking grave. It seems likely, but it’s not a sure thing.

Skilled wayfinders were able to sail across thousands of miles of open ocean on canoes as early as 1500 BCE. Navigators like Mau Piailuk of Satawal, in Micronesia, revived these traditional navigational techniques in the 1970s. The navigator would lie inside the hull of the canoe and feel the long, unbroken swells that are produced by far-off trade winds. If those swells hit a concealed island, they create a counter-swell that an experienced navigator can detect 20 or 30 miles out, even though the island itself remains invisible.

In China, during the Three Kingdoms era, Chinese engineers like Ma Jun constructed a two-wheeled cart that was capped by a little man whose outstretched arm always pointed toward the south. Differential gears, connected to the two wheels, rotated the figure in the opposite direction of the cart’s turn, such that the arm maintained its bearing while the vehicle moved on level terrain. There were no magnets used. Errors would build up over time due to wheel slippage, so the crew would need to reset the figure at solar noon.

In 1757, the British naval officer John Campbell modified the earlier octant design to make navigation easier for sailors. By using a movable mirror, a navigator can reflect the image of a star into a small telescope and align it with the horizon. The double reflection allowed a 60-degree frame to measure angles up to 120 degrees, which provided the latitude. Longitude was then determined by combining it with the precise time given by a ship’s clock.

Traditional navigators of the Santa Cruz Islands, Solomon Islands, sometimes sailed under cloudy skies without stars to navigate by. On such nights, they looked for te lapa, “the flashing”: a trail of light a few feet below the water, leading toward or away from land. Navigators like Teakei of Taumako were said to have been able to sight islands as far as 80 nautical miles out using te lapa. Scientists still don’t know exactly what causes the glow.

Compasses spin erratically near the magnetic poles, and the sun may not rise for weeks. A. H. Pfund’s 1948 sky compass, built into the roof of an aircraft, sensed the pattern of polarization in scattered skylight to determine the direction of the sun within about one degree, even when the sun was seven degrees beneath the horizon. It enabled Scandinavian Airlines to operate its first commercial transpolar route, between Copenhagen and Los Angeles, in 1954.

Navigators of the Arabian Sea, Persian Gulf and Indian Ocean like Ahmad ibn Mājid, a 15th-century navigator, sailed the Arabian Sea with a kamal, which is a wooden card with knotted string. He held it between his teeth and pulled it out at arm’s length until the card’s lower edge lined up with the horizon and the upper edge with the North Star, Polaris. The knot he kept clamped in his teeth indicated the height of the star, hence his latitude, never his longitude.

When Inuit, Iñupiat, and Yupik travelers crossed Arctic Canada, Alaska, and Greenland, they moved across tundra that was flat and featureless enough to make getting lost easy. So they built inuksuit, stacked stone markers. The word means “that which acts in the capacity of a human.” Open stone windows or elongated pointer stones indicated mountain passes, safe boat channels, or food caches. Over 100 ancient ones are still standing at Inuksuk Point on Baffin Island.

When ocean sailors needed to measure their speed, they tossed a weighted, pie-shaped board, called a chip log, which floated vertically like a temporary anchor, over the stern of the ship. A sailor counted the number of knots in a knotted line that passed through his hands while a measured amount of time elapsed from a short sandglass, then reeled the line back in. The count was the speed through the water, which is why we still refer to speed as “knots.”

Between 1928 and the late 1950s, over 400 ground stations around the US sent out a dot-dash tone on a radio signal in one part of the sky, and a dash-dot tone on another. Where the two met, pilots could hear a continuous 1,020 Hz tone. They kept the plane flying “on the beam” by keeping that sound in the middle of their earphones. There was no screen or needle, just a pure hum in the dark.

When a blizzard raged, or it was a winter night over the vast Arctic, the Inuit had no visual landmarks to see, nor stars to navigate by. Strong winds, however, blew the snow into straight, hard ridges known as uqalurait (“tongue-shaped drifts” in Inuktitut). Inuit hunters learned to feel these ridges under their boots or under the runners of their sleds and used them to maintain a straight path across the landscape, even when visibility was zero.

In the 1st century CE, Han dynasty scholars, surveyors, and diviners used the spoons described by Wang Chong in his Lunheng. They were made of lodestone, a rock with naturally occurring magnetic properties, and balanced on a smooth bronze plate inscribed with the compass points. The low friction of its bowl meant that it would rotate easily to point toward geographic south, guided by Earth’s magnetic field. Unfortunately, it was too big and heavy to be of much use on a rolling ship.

Paper and ink didn’t fare well on wet decks in the North Sea, Baltic, or Atlantic, and many helmsmen were unable to write anyway. The traverse board solved this problem: a wooden board featured a carved compass rose with rings of peg holes, one ring for each half hour of a watch. By inserting wooden pegs in the appropriate holes, the helmsman recorded the course he had steered and the speed alongside. At the end of his watch, the ship’s master transcribed this information into the ship’s logbook.

Without reliable timepieces, European seafarers relied on a handheld device called a nocturnal. A sailor used the nocturnal to sight Polaris, the North Star, through a hole in the center, and then rotated an arm to align it with a nearby “guard” star. The position of that arm on an inner dial gave the local time. That was precise enough to keep a watch and predict the tides. The nocturnal worked only in the Northern Hemisphere, where Polaris is visible.

The low coral atolls of the central Pacific lie only a few feet above sea level, and they cannot be seen from a canoe at more than ten miles out. Yet the bright sand of the lagoon and shallow turquoise water bounced sunlight upward, giving their undersides a pale green or yellow tint that Kiribati navigators called te aka. The reflected color told navigators where to look for atolls 30 to 50 miles beyond the horizon, provided there was some cumulus cloud cover.

In the age of the Greek historian Herodotus and well into the 20th century, coastal pilots used a bell-shaped lead on a rope marked off in fathoms. They lowered the lead to the ocean floor by paying out line and reading the marks. The hollow base was packed with tallow grease, which collected sand, shells, or mud from the sea bottom. By matching the bottom type and depth to a known stretch of coast, the pilot could figure out where they were. A clean lead was a sign of hard bottom, a rocky ledge or reef, but not a sign that the lead had failed to reach bottom at all.

Portuguese and Spanish navigators of the Age of Discovery, like Vasco da Gama, who set sail for India in 1497, needed a version of the astrolabe, a star-mapped instrument originally used on land, that could survive the wind on a moving ship. A heavy brass ring with wide, cut-out spokes allowed gusts to pass through, hanging steadily from a thumb ring. To take a reading, the navigator rotated the sighting arm to the sun at noon or Polaris and looked down.

First mentioned by mathematician Levi ben Gerson in 1342 for land astronomy, the cross-staff was later used by mariners like Henry Hudson for seafaring navigation. A navigator would hold one end of the staff to his eye and move a cross-piece or vane up or down on the wooden rod until the top and bottom edges of the cross-piece lined up with the horizon and a desired star. This reading indicated the ship’s latitude, but looking toward the sun to get the measurement could cause severe eye damage. The threat of eye damage led English navigator John Davis to come up with the back-staff in 1590.

A crosswind will cause a plane to drift sideways, and thus will invalidate any course charted by compass and time alone. Charles Lindbergh flew solo across the Atlantic in 1927, and to navigate he had a drift sight, a tube running through the floor of the fuselage with a rotating grid of glass in it. Waves or land features passing over the grid would appear to move. Lindbergh would rotate the grid until these features moved along the grid’s lines, indicating a drift angle. From this, he could adjust his heading and stay on track.

In the open ocean, navigators held a mental star compass called the paafu, with 32 “houses” defined by the rising and setting points of various stars, which they used only for direction-finding. A second skill was used for determining one’s position, based on certain zenith stars that are found directly overhead at only one latitude. If Hōkūleʻa, the Hawaiian name for Arcturus, was directly overhead, the navigator would know that his vessel was on the latitude of Hawaii, which is 19 degrees north, entirely from memory.

This content was created with the help of AI.