Golestan province sits in the north of Iran, on the south-eastern corner of the Caspian Sea, with Turkmenistan along its northern border. Its capital, Gorgan, was called Astarabad until 1937, and the province itself was carved out of Mazandaran only in 1997. The weaving half of it is not the humid farmland and forest along the Caspian but the dry plain to the north, TurkmenSee in the carpet dictionary Sahra, whose market towns are Gonbad-e Kavus, Bandar-e Torkaman and Aq Qala. That plain is the Iranian homeland of the YomutSee in the carpet dictionary and Goklan Turkmen, and the weaving that carries the region's name is Turkmen weaving.

Its name sends buyers in the wrong direction. GolSee in the carpet dictionary means flower and -stan means place, so Golestan reads as flower garden, and the trade sometimes borrows the word for rose-garden designs that have nothing to do with the province. What a flower means on this steppe is a different thing: the gul, an octagonal emblem repeated in ranks across the field. The word is usually explained as the Persian one for flower, but what it names is a device held in the weaver's memory and drawn in straight lines, not a botanical study of vines and blossoms.

Turkmen weavers came into Iran from the Central Asian steppe east and north of the Caspian, brought the design with them, and kept making it once they had settled on the Iranian side of the frontier. Their presence on that frontier was organised and militarily serious: the Safavid shahs settled Kurdish fighting tribes further east, on the border above Mashhad, expressly to hold the line against Turkmen pressure. Settling changed the politics more than it changed the weaving. Rugs made in Turkmen Sahra still come out of a tribal tradition, on a tribal loomSee in the carpet dictionary, in families working from memory rather than from a workshop cartoon.

Field layout follows one rule: rows of guls, evenly spaced, running out to the edge of the field with no central medallionSee in the carpet dictionary. Borders are narrow and stacked, built from small geometric bands rather than scrolling vines, so they frame the repeat instead of competing with it. In older pieces each tribe kept its own gul to itself, and an experienced eye could name the weaver's tribe from the pattern alone. That restriction has gone. Weavers now combine guls from several tribes in a single rug, which is the most visible difference between older work and current production.

Prayer rugs are a second speciality of these weavers. The design is unidirectional, built around a mehrabSee in the carpet dictionary, the arched doorway that gives the rug a top and a bottom; tribal versions tend towards a plain outlined arch rather than the columned architecture a city workshop draws. A piece like this hangs as well as it lies, which is why so many of them end up on a wall, where the single orientation stops being a limitation and the arch reads the way it was drawn.

Colour is the quickest way to identify the type. Grounds are deep red, reddish brown and occasionally cream, and those three cover nearly everything the region produces. Green, blue, black and beige appear as highlights inside the guls and along the border bands, almost never as a field colour. A red-brown ground under an all-over octagonal repeat is recognisable across a room. Colour has traditionally come from plant dyes gathered locally, which is why the red of one rug rarely matches the red of the next, and why a larger piece can show gentle horizontal banding where one dye lotSee in the carpet dictionary gave out and another began.

WoolSee in the carpet dictionary here comes from karakul sheep, a breed that grows two coats at once, a coarse outer fleece over a finer, softer one beneath it. Turkmen weavers use the inner fleece, which is what gives the pileSee in the carpet dictionary its close, dense handle rather than a plush one. Construction is normally wool throughout, wool warpSee in the carpet dictionary and weft under a wool pile, and a cotton foundation does occur but is the exception rather than the standard. Spring shearing gives the best fleece of the year, and the quality of a rug's wool tracks the grazing behind it rather than anything done at the loom.

At the fine end sit the Yomut pieces, the most highly regarded weaving of this tradition, and they belong to this steppe on the Iranian side of the border as much as to the Turkmen country north of it. Some are built on a silk foundationSee in the carpet dictionary instead of wool. The silk sits in the warp and weftSee in the carpet dictionary only, the pile stays entirely wool, and the point of it is densitySee in the carpet dictionary: a thinner, stronger foundation lets the weaver set more knots into the same area and draw the guls in more detail than a wool foundation allows. These pieces almost never carry a signature.

Pile is kept low to medium and never deep, partly because a fine repeat only reads properly when the wool is cut short. That makes these rugs practical where a thick carpet is not: they sit flat under a door that has to swing over them, take a chair leg without holding the dent, and work along a hallway or at the edge of a kitchen. A wool foundation also keeps the rug supple rather than board-flat, so it will follow a step or an uneven floor instead of fighting the shape.

Sizes run small. A tribal loom is built to be taken apart and carried, which limits the width of what can be woven on it, so this tradition produces far more scatter rugs, runners and modest area sizes than room-filling carpets. The same looms turn out the household weaving that was much of the point in the first place, the storage bags and tent trappings, along with flatweaves beside the knotted pile. A very large carpet in this drawing is likelier to have come off a workshop loom somewhere else than off a loom on this steppe.

The gul travelled a good deal further than the tribe did. Much of what is sold worldwide as BokharaSee in the carpet dictionary is workshop production in Pakistan and Afghanistan, wool pile on a cotton foundation, copying Turkmen drawing with factory evenness and a wider choice of field colours; the name itself points at a Central Asian market city where Turkmen rugs were once traded, not at anywhere they were made. The tribal original is wool on wool, slightly irregular where a hand-drawn repeat drifts, and coloured from a local dye pot. Telling the two apart matters more with this type than with almost any other Persian rug.

A Persian rug is an Iranian rug — a rug hand-knottedSee in the carpet dictionary in Iran — and the tradition behind it is the oldest documented anywhere. The earliest surviving carpet, the Pazyryk rugSee in the carpet dictionary, was found preserved in a frozen burial mound and dates to the fifth century BC — roughly 2,500 years ago — and it is already accomplished work, not a beginner's craft. What began as warm, hard-wearing floor coverings for tribal households grew, over those centuries, into the art form that every other rug-weaving country has borrowed from.

Two later chapters shaped what a Persian carpet looks like today. Under the Safavid dynastySee in the carpet dictionary, from 1501 to 1732, the court promoted weaving alongside painting and calligraphy, and the workshops of Tabriz, HeratSee in the carpet dictionary, Kashan and Kerman produced the masterpieces that now sit in museums. This is when the great central medallionSee in the carpet dictionary appeared, and when designs grew elaborate enough that a separate designer — often a miniature painter — drew the pattern onto a cartoon for the weaver to follow. The second chapter came in the nineteenth century, under the Qajar dynastySee in the carpet dictionary, when production reached its historical peak, exports to Europe and America boomed, and the workshop industry whose descendants still weave today took its modern shape.

The trade sorts Persian rugs into three families. City rugs — Tabriz, Kashan, Kerman, Nain, Isfahan — are woven in workshops from a drawn design, carry the highest knot densities and come in the widest range of colours, sizes and patterns. Village rugs such as HerizSee in the carpet dictionary, BakhtiariSee in the carpet dictionary and KarajaSee in the carpet dictionary sit in between, mostly geometric and largely woven from memory. Tribal rugs — Baluch, TurkomanSee in the carpet dictionary, QashqaiSee in the carpet dictionary, each named after the people who weave it — are made on small portable looms, so they run smaller, and their bold geometric drawing comes from the weaver's own head rather than from paper.

The design vocabulary draws on a deep stock of motifs: Shah AbbasiSee in the carpet dictionary palmettes, flowing arabesques, the small repeating Herati patternSee in the carpet dictionary, medallions, garden and tree-of-life compositions. These combine with regional habits into styles a practised eye can place at a glance, from the bold geometric medallions of Heriz to the fine curvilinear florals of Isfahan.

The classic palette is built on natural dyes: madderSee in the carpet dictionary reds, indigo blues, saffron yellows and the soft whites of undyed woolSee in the carpet dictionary, settled into combinations refined over centuries. Natural dyes age gracefully, mellowing into the patina that older rugs are prized for, and slight shifts of tone between dye batchesSee in the carpet dictionary — the effect called abrashSee in the carpet dictionary — are a mark of small-batch natural dyeing, not a flaw.

The pileSee in the carpet dictionary is almost always woolSee in the carpet dictionary, and in a Persian wool rug the wool itself decides much of the quality. The best fleece comes from high-altitude flocks, where it grows thicker and richer in natural oils; spring-sheared wool beats the autumn clip, and hand-spun yarnSee in the carpet dictionary gives a finer, softer thread than machine spinning. Fine pieces add silk highlights to a wool pile, and at the very top sits the Persian silk rug, woven in pure silk. Foundations are usually cotton in city weaving, wool in tribal and older pieces, silk at the very top of the range.

Every knot is tied by hand, one at a time, in one of two forms: the asymmetric Persian knotSee in the carpet dictionary, usual in central and eastern Iran, or the symmetric Turkish knotSee in the carpet dictionary, common in the north-west ever since Seljuk weavers introduced it in the eleventh and twelfth centuries. A large rug holds in the region of two million knots and can occupy a weaver for about a year.

Knot densitySee in the carpet dictionary is the figure newcomers fixate on, and the finest silk-foundation pieces do reach as much as 1,000 knots per square inch. But densitySee in the carpet dictionary only matters as far as the drawing demands it: a curvilinear Isfahan needs a fine weave to stay sharp, while a geometric Heriz is famously durable at a modest count. Material, symmetry, colour harmony and condition say more about quality than any single number.

Persian carpets settle into modern rooms as naturally as classical ones, as a focal point in a living room, a foundation under a dining table or a quieter accent in a bedroom. Care is undemanding: gentle vacuuming without a rotating brush, an occasional turn for even wear, and a professional wash about every five years — sooner in a hallway or entrance, less often in a quiet room.

A hand-knotted Persian rug tends to outlast its owners. Pieces a century old regularly survive in fine condition, their colours settled and their pile supple, often looking better than when they left the loomSee in the carpet dictionary. A well-chosen, well-kept rug holds its worth and passes down as a family heirloom rather than being replaced — which is precisely what the knots, the wool and the dyes were always for.