Most people come into Shikoku from Tokyo or Osaka via Okayama on the shinkansen. From Okayama Station, take the JR local 25 minutes south to Uno Port, then the 20-minute ferry across to Miyanoura Port on Naoshima. As of writing, the foot-passenger fare is ¥370 one-way. If you’re starting from Takamatsu instead, there’s a longer 60-minute ferry (¥680) or a 30-minute high-speed boat (~¥1,590).

What to actually see in one day

Naoshima fits into a single day if you plan tightly. The three sites that matter most:

• Chichu Art Museum — Tadao Ando’s underground museum housing Monet’s Water Lilies in a daylit room and James Turrell’s Open Sky. Reservation required — date- and time-specific. Weekday tickets ¥2,500 online (¥2,800 on-site); weekends ¥2,700/¥3,000. Closed Mondays. Book directly on chichu.jp before you arrive — on-site sales aren’t guaranteed.
• Yayoi Kusama Yellow Pumpkin — the photographable one. Sits on a pier near Tsutsuji-so. Free, outdoor, busy at midday.
• Benesse House Museum & the Red Pumpkin — the red one is at Miyanoura Port, free, photogenic, and a useful bookend before catching the ferry back.

Getting around the island

Bicycle rental is the standard move. Several shops near Miyanoura Port rent regular and electric bikes for the day. If you don’t trust the gradient (Naoshima has more hills than the photos suggest), the town shuttle bus connects Miyanoura → Honmura → the museums for ¥100 a ride. Save energy for the museums — Chichu alone takes 90 minutes if you’re paying attention.

Where to sleep tonight

You have a choice. Stay on Naoshima (limited rooms, atmospheric, books out months ahead — Benesse House if budget allows, Tsutsujiso or local minshuku if not). Or ferry back to Takamatsu for the night, which gives you a Sanuki udon dinner and an easier start to Day 2. I usually choose Takamatsu — the museum is the experience; Naoshima at night is quiet to the point of stillness.

Today is a two-stop day, both in Kagawa Prefecture. Mornings belong to Ritsurin. Afternoons belong to a long walk uphill.

Ritsurin Garden — the daimyo garden the Michelin Guide gave three stars

Built over a century starting in 1625 by the Matsudaira lords of the Takamatsu domain, Ritsurin is one of the few daimyo gardens to survive the Meiji restoration intact. It opens at sunrise (around 5:30–7:00 depending on the season; check the official site close to your visit) and is genuinely empty for the first hour. Admission is ¥410. Walk the south garden first — the Hiraihō hill view of the south pond and arched bridge is the postcard.

From Takamatsu Chikko Station, the JR Kotoku Line takes you to Ritsurin-koen-kitaguchi in about 5 minutes. From there it’s a 5-minute walk to the gate. Allow 90–120 minutes for the garden itself.

Lunch: Sanuki udon, the right way

Kagawa is the udon prefecture. The local style — Sanuki udon — is firmer, chewier, and usually self-served at counter shops where you grab your own bowl, top it from a tray of tempura, and pay ¥400–700. Two reliable picks near Takamatsu Station: Tsuruichi for the morning kake bowl, Mawaru Udon for late lunch. If you only have one bowl in Shikoku, have it here.

Kotohira-gu — the long walk up

By early afternoon, take the JR Dosan Line south from Takamatsu to Kotohira Station (~60 min, ¥870). The town exists almost entirely for the shrine.

The walk to Kotohira-gu’s main shrine is 785 stone steps. To the inner shrine (Okusha), it’s 1,368 total. There’s no cheating: no ropeway, no escalator. Take the climb at your own pace — it’s broken up with smaller shrines, a noh stage, and benches.

I’d budget two hours up and back. The main shrine itself sits at the 785-step mark with a panoramic view of the Sanuki plain. From here you can either turn around or push on.

The remaining 583 steps to the Okusha (Itsutamajinja) thin out fast. Most visitors stop at the main shrine. If you make it to the inner shrine, you’ll get a small wooden plaque as proof and, more usefully, the entire complex more or less to yourself.

Sleep in Kotohira itself if you’d rather wake up unrushed for Day 3 — the ryokan town below the shrine has good onsen options. Or backtrack to Takamatsu.

The Iya Valley is, in my opinion, the single most striking landscape in Shikoku. It’s also the hardest to reach. There is no train. The bus from Oboke Station is sparse. And the gorge roads are narrow enough that even Japanese drivers slow down. If your itinerary allows, this is the day to switch to a rental car — pick one up in Takamatsu or at Oboke Station via a local agency.

Kazurabashi — the vine bridge

Built (and rebuilt every three years) from Actinidia arguta vines and reinforced with hidden steel cable, the Kazurabashi is one of three remaining vine bridges in Iya. The wooden slats are spaced wide enough that you see the river below as you walk. Toll is ¥550 (adult). One-way crossing only — you can walk back via the road bridge downstream. Hours seasonal, roughly 8:00–17:00. Note 2026 Evening illuminations run 19:00–21:30 in summer, but no crossing is permitted during the lit hours.

Other stops on the gorge road

• Oboke / Koboke Gorges — sightseeing boats run from Oboke Station (about ¥1,500 for a 30-minute loop). Worth doing if you have a slow afternoon.
• Peeing Boy statue (小便小僧) — a small bronze figure on a 200m cliff edge, modeled after local children who reportedly used to test their nerve. Quick stop, free, photogenic in a strange way.
• Iya Onsen Hotel — even if you’re not staying, the hotel’s private cable car descends into the gorge to a riverside rotenburo. A ¥1,800 day-use ticket gets you down. Closed Jan 5–15, 2026 for maintenance

Where to sleep tonight

If your budget allows, this is the night to splurge on a ryokan. Hotel Iya Onsen is the only full-scale hotel in the gorge and the rotenburo experience is unmatched. Iya Bijinyu is the alternative. Both are bookable internationally. If you’d rather drive on, Awa-Ikeda is the next train town with reliable accommodation.

From Iya Valley, work your way west to Matsuyama. By car, it’s roughly 3 hours via the Tokushima Expressway. By train, route via Awa-Ikeda → Okayama → Matsuyama on the JR Yosan Line takes 4–5 hours and is honestly painful — the car is the better option here.

Matsuyama Castle — the keep that survived

Built in 1602–1627, partially burned in the 19th century, partially restored, and somehow still intact through the 1945 firebombing of Matsuyama. It’s one of twelve original castle keeps in Japan — the rest are concrete reconstructions. Take the ropeway up Mt. Katsuyama (¥520 round trip) or walk it (30 minutes). Castle admission ¥520. Allow 90 minutes inside the keep — six floors, wooden ladders, no elevator.

Dogo Onsen — Japan’s oldest hot spring

A 20-minute tram ride east on the Iyotetsu line drops you at Dogo Onsen Station. The bathhouse you came for — Dogo Onsen Honkan — is a 5-minute walk through a covered shopping arcade.

The Honkan reopened completely in July 2024 after a phased conservation project that ran more than five years. All three baths — the main Kami-no-Yu, the smaller Tama-no-Yu, and the upstairs resting rooms — are now operational. Basic bath ticket ¥460. Numbered entry at peak times. Two newer companion bathhouses, Asuka-no-Yu (6:00–23:00) and Tsubaki-no-Yu (6:30–23:00), sit a 2-minute walk away if the Honkan queue is long.

Dinner: Iyo-no-Yado, sea bream, mikan

Ehime is the citrus prefecture. Mikan, iyokan, kawachi-bankan — the orange you’d be happy to eat any day of the year is a local cultivar. For dinner, look for a kaiseki-style ryokan along the Dogo arcade or one of the seafood izakaya near Okaido that serve tai-meshi (sea bream rice) — Matsuyama has two distinct versions of the dish, both worth ordering.

Last day. From Matsuyama to Kochi, the JR Shikoku Yodo Line / express alternatives take 2.5–3 hours; by car it’s about the same via the Matsuyama Expressway. Kochi is the most distant of the four prefectural capitals from the rest of Japan, and it shows: the city has a slower rhythm, a wider main street, and a culture more centered on its harbor and its history of dissent than on any imperial capital.

Kochi Castle — the only one of its kind

Twelve castles in Japan still have their original Edo-period donjons. Kochi is the only one that also retains the honmaru-goten, the lord’s residence. You can walk through both. Admission ¥420. 8:30–17:00 (last entry 16:30). Allow 90 minutes — the keep has six floors connected by steep wooden stairs and the view from the top is the best one in the city.

Lunch at Hirome Market

A 5-minute walk from the castle gate is Hirome Market — a covered hall of about 60 food stalls inside the Obiyamachi arcade. The reason to come: katsuo no tataki, the Kochi specialty.

Tataki, done correctly, is bonito loin held over a straw fire for about 30 seconds — long enough to sear the outside and smoke the surface, short enough to leave the inside fully raw. Several stalls inside Hirome do live demonstrations. Myojinmaru is the most famous; Daikokudo is the local pick. Both serve katsuo with raw garlic slices, sea salt, and ponzu — the salt version is the local way; ignore the soy if you can. Hours ~8:00–23:00 weekdays/Saturday, 7:00–23:00 Sunday (varies by stall).

Katsurahama and the Ryoma statue

Take the My Yu Bus tourist loop or the Katsurahama bus from Kochi Station (~30 min, ¥670 one-way). The 1-day My Yu pass at ¥1,300 covers both directions plus Godai-san if you want the long version.

Sakamoto Ryoma — born 1836, assassinated 1867 — was the samurai who arguably did more than anyone to broker the alliance that ended the Tokugawa shogunate. The statue at Katsurahama, erected in 1928, looks south toward the ocean he kept urging the Tokugawa to reckon with. Free to visit. The beach itself isn’t for swimming (rough surf, dangerous currents) but the cliff walk along the headland is half an hour well spent.

Heading home

From Kochi, the simplest exit is the JR Dosan / Nanpu Limited Express to Okayama (2h 30m), then shinkansen back to Tokyo / Osaka. If you flew, Kochi Ryoma Airport has direct flights to Haneda, Itami, and Fukuoka. Kochi to Tokyo by air is 80 minutes — the fastest way out of Shikoku, by a wide margin.