A city of street stalls and straw-seared bonito
Kochi, on the Pacific side of Shikoku, sits where bonito swim close to shore on a warm ocean current, and its Sunday market has been held on the same street for more than 300 years. In the morning, snack your way along the stalls and climb to the castle; at night, eat katsuo no tataki, bonito seared over burning straw, with local sake. The market runs only on Sundays and Kochi is about three and a half hours from Osaka by train, so stay on Saturday night.
A street market of about 500 stalls running some 1 km east from the castle gate, where farmers sell vegetables, kitchen knives and garden plants. Snack as you walk on imo-ten, sweet potato fried in batter, and inaka-zushi, country-style sushi made with mountain vegetables instead of fish. Go in the morning, since stalls start packing up in the afternoon.
Buy a dish from one stall and a drink from another, then sit wherever there is room: sharing a table with strangers is normal here, and people often end up talking. At the Myojinmaru counter, you can watch bonito seared in a burst of straw flame. Evenings get very crowded, so come early to find a seat.
An izakaya, a Japanese pub, where you sear the bonito yourself over a straw fire, then slice it into tataki and eat it while it is still warm and smoky. It opens only in the evening, and booking ahead is wise; the booking page is in Japanese, so a hotel can help.
One of the twelve castles in Japan whose wooden keep survives from the Edo period, with the lord's residence still standing beside it. From the top of the keep you look down on the Sunday market street and the city. The path up starts at the western end of the market, so the two make an easy pair.
A museum across from the castle's main gate about life in Tosa, the domain that once ruled this region, with windows that frame the castle on its hill. On Sundays it opens at 8 am, earlier than most museums, so you can step in between the market and the castle.