Oaxaca holds one in four of Mexico's municipalities, and the explanation is the relief

One figure usually reads as administrative trivia and is in fact a physical map in disguise: Oaxaca has 570 municipalities. All of Mexico has 2,462. That is to say, almost one in four municipalities in the country sits in a state that covers less than five per cent of its surface. Mexico's smallest municipality is here too: Natividad, at 2.2 square kilometres.

This is not a legal quirk. It is what happens when, for centuries, the ground stops two neighbouring villages from sharing a square, a graveyard or a mill.

01 Three mountain ranges that cross

Oaxaca is where Mexico's relief tangles. The Sierra Madre del Sur arrives from the west along the Pacific coast; the Sierra Madre de Oaxaca comes down from the north; the Sierra Atravesada closes off the east, on the way to the isthmus. The three tie together in an orographic knot, the Nudo Mixteco, and branches run out of it in every direction.

Two numbers measure the result well. The state's average altitude is 1,644 metres, higher than that of any European capital. And a little over half its surface is properly mountainous: not gentle hills but slopes that climb a thousand metres in a few kilometres. The highest point, Cerro Nube, reaches 3,720 metres less than sixty kilometres in a straight line from the sea.

In a territory like that, the unit of life is not the region. It is the valley. Each hollow has its water, its strip of workable land and its closed horizon; and for centuries, getting to the next valley cost a full day on the road.

02 One in four of the country's municipalities

That is where the opening figure comes from. When Mexico drew its municipal map, in Oaxaca there was no way to group anything: each settlement had spent generations running its own land, its own water and its own calendar, and none was willing to depend on the one next door, reachable only by crossing a range.

The comparison that explains it best sits at the other end of the country. Baja California covers more ground than Oaxaca and is divided into seven municipalities. The difference is not population or wealth: there, the terrain lets you govern a thousand kilometres from a single office, and here it will not let you govern two valleys from the same one.

The state is also split into eight regions — Valles Centrales, Sierra Norte, Sierra Sur, Mixteca, Cañada, Papaloapan, Istmo and Costa — and those eight are not a desk invention: each matches a distinct physical compartment, with its own altitude, climate and pantry.

03 Fifteen languages and 176 variants

The same logic can be heard before it is seen. Mexico's official catalogue of indigenous languages records 364 linguistic variants across the country. Oaxaca accounts for 176: almost half, grouped into fifteen languages and five separate families. Zapotec, Mixtec, Mazatec, Mixe, Chinantec, Chatino, Triqui, Cuicatec and several more.

The interesting number is not the count of languages but the count of variants. A variant appears when two communities that spoke the same thing stop hearing each other daily for generations. In Oaxaca there are villages twenty kilometres apart on the map and four hours apart on the track, and that distance — the real one, measured in hours — is what manufactures variants.

Put another way: the 570 municipalities and the 176 variants are the same fact told twice, once in the civil register and once in the dictionary.

04 The one place where the ground opened up

There is one exception, and that is where the city is. In the centre of the state, three arms of valley — Etla to the north, Tlacolula to the east, Zimatlán and Ocotlán to the south — converge in a wide plain at around 1,550 metres. It is the only place in Oaxaca where the ground gives way, and it is exactly where everything that needed space settled.

Around 500 BC, a ridge sitting right at the junction of those three arms was levelled by hand to build a plaza on top of it. Monte Albán stands at 1,940 metres, some 400 above the valley floor, and from its esplanade you can see all three branches at once. It was not a position chosen for the view: it is the only one from which the three roads could be watched.

That same triangle carries the everyday life of the state today. It also carries its most useful invention: market days. Instead of one big permanent market, the valley towns split the week — Wednesday in Etla, Thursday in Zaachila, Friday in Ocotlán, Sunday in Tlacolula — so that a single circuit of traders can work all of them without repeating a day. It is a network designed by the relief: one central market would have left half the population out.

05 What it costs to cross a range

If anyone doubts that the relief is still in charge, a recent piece of engineering puts a number on it. Linking the state capital with the Pacific coast required a motorway of 104.3 kilometres with ten bridges, three viaducts and three tunnels. It took nineteen years to finish and opened to traffic in February 2024.

The effect was immediate: the run between Oaxaca City and the coast fell from about six and a half hours to about two and a half. A hundred kilometres of asphalt took four hours off a journey. That is the exact measure of what the range had been charging in toll all along, and of why coast and valley have worked for centuries almost as two separate states.

06 What this changes for the traveller

The first consequence is that in Oaxaca kilometres are useless for planning. You have to count in hours and double whatever the map suggests. A village that looks close may be on the far side of a 2,500-metre crest and a road of continuous curves.

The second is that it pays to pick one compartment and stay in it. The state is not toured: it is visited by region. The Central Valleys from a base in the city are a complete trip; the Sierra Norte is another; the coast is a third, and it is now two and a half hours away, not seven. Attempting all three in a week means spending the week on the road.

The third is about expectation. The variety celebrated here — of kitchens, weaves, clays, languages — is not decorative abundance: it is the result of hundreds of communities having had to solve everything on their own for a very long time. When two neighbouring villages sell two different versions of the same dish in one market, they are not competing. Until recently they barely saw each other.