Kagawa

This is the driest corner of a wet country, rice was historically difficult here and wheat was not, and the result is a prefecture with several hundred udon shops in it. The format matters as much as the food: many of the best are self-service operations in plain industrial buildings where you take a bowl, tell them the size, add your own broth and toppings from a counter, and pay by what is on the tray.

The trap is the hours. A good number open very early and are shut by the middle of the afternoon, because they were built around people eating before or between work rather than around a lunch service. Plan an early breakfast or an early lunch, not a leisurely one at two o'clock. Several of the most highly regarded shops are also on farm roads with no bus service, which is why local drivers run guided noodle circuits.

Takamatsu is reached by the Marine Liner from Okayama in about an hour, crossing the Seto-Ohashi bridge, which makes the Sanyo Shinkansen the practical approach from Tokyo or Osaka. Takamatsu Airport is 40 minutes from the city by bus. The islands run on ferries from Takamatsu and Uno — Naoshima takes about 50 minutes by car ferry or half that by fast boat — and the timetables are the real constraint on any island day, so build the plan around the last sailing. Kotohira is an hour by JR or the Kotoden private line. Shodoshima needs its own ferry and a car or bus once you land.

The art islands are the reason many people come, and every one of them is reached by boat on a fixed schedule with gaps of hours between crossings. That makes an island day unlike a normal day out: the constraint is not how long you want to stay but which departures exist, and the last one back is the hard edge of the whole plan.

Look up the return times first, then decide what fits inside them, then buy the outward ticket. Museums and installations on the islands often need a specific slot and sometimes need booking, and they are spread out enough that walking between them takes real time — bicycles and local buses exist for that reason. Missing the boat is not a minor inconvenience; on the smaller islands the accommodation is limited and may well be full.

Two days, and Kagawa is the smallest prefecture in Japan, which makes it unusually efficient. Takamatsu has one of the finest gardens in the country at Ritsurin, the udon that the prefecture is genuinely famous for is everywhere, and the art islands are a ferry from the harbour.

Distances are small: Takamatsu to Kotohira, with its long stone staircase up to a major shrine, is about an hour by train. The ferry to Naoshima is fifty minutes; to Shodoshima about an hour. Everything is inside a short radius.

Two days does Takamatsu, the garden and one island. Three does the garden, two islands and the shrine. This is also the easiest Shikoku prefecture to reach — the bridge from Okayama puts Takamatsu under an hour from a shinkansen station, which is why it is the usual entry point to the island.

The art islands during a festival year, unless you have booked — the triennial event fills every room and every ferry, and the queues at the major installations are long. In non-festival years the same islands are quiet on a weekday.

Museums on Naoshima close on Mondays, which is the standard wasted day here. Otherwise the Inland Sea climate is one of the mildest and driest in Japan and there is no bad season. August is hot but the islands catch a sea breeze, and winter is bright and clear.

Sanuki udon is the point: firm, square-edged noodles served kake with hot broth, bukkake with a splash of concentrate, or cold with soy, and the cheapest bowls run to a few hundred yen. Many of the best shops are hard to reach without a car, which is why udon taxi tours exist. Shodoshima has grown olives since 1908 and produces oil, plus olive-fed beef and yellowtail. Honetsuki-dori is a whole grilled chicken leg, heavily peppered, from Marugame. Wasanbon, a fine-grained sugar refined by hand here, is pressed into small moulded sweets for tea.

This is one of the driest and mildest corners of Japan: January highs near 10°C, little snow, and low rainfall throughout. Summers are hot above 33°C. The Setouchi Triennale runs across three seasons of its festival years and the island ferries are packed then; outside those years the same islands are quiet, and Naoshima's museums close on Mondays. Ritsurin Garden is worth a spring or autumn morning and opens near sunrise. Olives on Shodoshima are harvested in October and November. Ferry crossings are occasionally cancelled in winter wind or summer typhoons.

Trains and ferries. Takamatsu is compact, the local lines reach Kotohira and the coastal towns, and the islands are all boats from the harbour. A car is unnecessary and on the small islands it is actively unhelpful — bicycles and the island buses are how people get around, and several of the ferries charge substantially for vehicles.

The one place a car helps is the udon pilgrimage: the best-regarded noodle shops are scattered across the countryside, several open only in the morning, and hitting four in a day is a driving exercise that locals treat as a legitimate day out. Rental bicycles are the modest alternative.

A first visit is Ritsurin Garden and the islands. The garden is a stroll garden of ponds, pines and a wooded hill behind it that was three hundred years in the making, and it is a short ride from Takamatsu Station; the islands are fifty minutes out and are the reason most international visitors come to Shikoku at all. Eat udon at least twice a day; it is genuinely different here and it costs almost nothing.

A second visit should be Shodoshima and Kotohira. The larger island has olive groves, a gorge with a ropeway and a village that puts on kabuki in a farmhouse theatre; the shrine at Kotohira is 785 steps up a mountainside with a town of old shops leading to the bottom of them. Neither is on the art-island circuit and both are better for it. Shodoshima's kabuki stage is still used by the villagers who own it rather than run as a performance for visitors, and the olive groves on the island were the first commercially successful ones in Japan.