Eight days in colonial Mexico: four highland cities where the empire came apart

Arrive and go no further than three hundred metres. The Jardin de la Union is a wedge of laurel trees clipped flat, built as the atrium of a seventeenth century convent, ringed with restaurant tables and with a bandstand in the middle that is genuinely in use most evenings.

On its edge is the best building in the city. The theatre is neoclassical outside, with bronze muses along the roofline, and then entirely Moorish inside: carved wood, red velvet and gilding that has nothing to do with the front of the building at all. It was opened in 1903 by Porfirio Diaz and it is still the main stage of the October festival.

Then go up. A funicular behind the theatre climbs the ravine wall in three minutes to the monument on the ridge, where the view is of the whole coloured bowl of the city with the church domes coming up through the roofs. Go before sunset, stay for the lights, and ride back down rather than taking the slope in the dark.

The morning is the independence story, and it happened in a grain warehouse two streets from the centre. In September 1810, a few weeks into the revolt, the Spanish garrison and the loyalist families shut themselves inside the granary with the treasury. The rebels could not force the door until a miner reached it under cover of a stone slab and set fire to it. Everyone inside was killed, and the four leaders of the revolt later had their heads hung in iron cages from the corners of the roof for a decade as a warning.

The building is now the regional museum, with the archaeology and painting of the Bajio alongside the independence rooms.

The afternoon is uphill. The Valenciana vein was the richest here, it ran for two centuries and it is still worked; the shaft, the hoist and the stone terraces above ground are all in place, and guided visits go down a section of the old workings. A hundred metres from the gate the count who owned it built a church as a thank-offering, and its three altarpieces are so completely covered in carved and gilded wood that the effect is nearer a jewellery box than a building. The two side by side make the argument about this city better than anything else could.

Take a mid-morning coach. The road climbs out of the ravine and crosses ninety minutes of dry, open, cactus-covered country before dropping into San Miguel, and it is a good introduction to how empty the Bajio is between its cities.

Arrive, eat, and start on the square. El Jardin is a rectangle of laurels clipped square as furniture with the parish church filling one end of it, and the church is why people come: a pink stone front of pinnacles and spires added in the nineteenth century by a self-taught local builder said to have worked from a picture of a European cathedral. It is absurd and it is wonderful.

Then the corner house where Ignacio Allende grew up. He was the cavalry officer who planned the revolt with the priest Hidalgo, he did not survive it, and the town took his name a few years after he was shot. The ground floor is furnished as a wealthy creole family kept it and the upper floor is the war.

Go north. Twelve kilometres out on the Dolores road stands a low white church in a village of almost nothing, and its interior is one of the strangest in Mexico: every wall and vault covered in painting and lettering, worked over decades by one artist and his workshop, dark, crowded, unrestored. People call it the Sistine Chapel of Mexico, which flatters the technique and rather undersells the effect.

It is a working pilgrimage site, not a monument, so there will be people praying and you should cover your shoulders. Minibuses run out from town and a taxi costs very little.

Then keep going up the same valley. There are warm mineral springs out here and the pools built around them are where San Miguel spends Sunday: five of them at the best known site, plus a tunnel that opens out into a domed grotto with the water falling in from above. Take a towel, take water, and give it the whole afternoon.

Back in town for the late afternoon, the former convent beside the square is now an art school with an unfinished Siqueiros mural on its ground floor, left where he stopped.

An hour on the road and you are in a different kind of city: flat, prosperous, businesslike on the outskirts and, in the middle, a small pedestrian grid of baroque convents and shaded plazas that almost nobody stops for.

Give the afternoon to one story. In 1867, after the French withdrew their army, Maximilian of Habsburg held out here with the last of his troops, was betrayed, and surrendered. He was court-martialled in a plain neoclassical hall beside the plaza, the same room in which, sixty years later, the delegates sat to write the constitution Mexico still uses.

He spent his last night in the convent on the hill east of the centre, a Franciscan house whose missionaries founded the chain of missions that runs all the way up into California, and which keeps a tree in its garden whose thorns grow in the shape of crosses.

Then out to the bare rise west of the centre, where he and two of his generals were shot on a June morning in 1867. His brother, the Emperor of Austria, later paid for a small memorial chapel on the spot, and there is a monument to the man who ordered the execution on the same hill. It is a strange, quiet, rather moving place to end a day.

Three hours south, out of the Bajio and into Michoacan, and the landscape gets green and volcanic on the way. Arrive in the early afternoon, drop the bags and walk out into a city that is a single colour.

The cathedral takes most of a block and it took most of a century to build, finishing in the seventeen forties. Two towers, flying buttresses, a tiled dome, and inside a silver font and a very large German organ. If it happens to be a Saturday, come back at around nine at night, when the front is lit in sequence and fireworks are let off the towers to an audience of half the city.

Straight across the road is the state government building, put up in the seventeen sixties for the diocesan seminary and now the governor's offices, which you can simply walk into. Go up the main stairs: Alfredo Zalce painted the walls and the vault above them with the history of Michoacan, and on an ordinary weekday nobody else is looking at them.

Start west of the cathedral at the old Jesuit college, an enormous eighteenth century building set around an arcaded patio with a fountain in it, now the city's main exhibition space. What is showing rotates between historic indigenous work and contemporary art; the courtyard on a bright morning does not change and is reason enough on its own.

Then the small house belonging to Jose Maria Morelos, the man the city is named for. He was a muleteer, then a country priest, and then the ablest field commander the independence war produced, and he was shot for it in 1815. The museum is plain and the house is modest, and together they say more about him than any statue in the country does.

Keep the late afternoon for the conservatory. There has been a music school here since the seventeen forties, which makes it one of the oldest in the Americas, it occupies a former convent around a rose garden, and its boys' choir was rebuilt last century on the Viennese model. Concerts are frequent and cost almost nothing, and when nothing is on you can generally hear rehearsal drifting out of the courtyard windows.

One last walk, due east, and it is the best hour Morelia has. Start where the avenue opens out at the bronze fountain: three Purepecha women holding a bowl of fruit above their heads, the version there now cast in 1984 after an earlier one disappeared.

Behind it the arches begin and run down the middle of the road for well over a kilometre, an eighteenth century aqueduct that brought water in from the hills and is now simply left there with traffic on either side and a lit walkway underneath. Walk it rather than looking at it from a taxi window.

At the far end, turn off for the Guadalupe sanctuary. Outside it is an ordinary church front. Inside, every surface was redone in soft pink, white and gold plaster, flowers and scrollwork climbing the columns and spreading across the vault, and there is nothing else like it in the country. Ten minutes, and it is the thing you will end up describing to people at home.

Then breakfast, then the airport or the coach.