Festa de São João do Porto

São João is Porto's night and it is unlike anything else in Portugal. Everyone is outside from evening until dawn on 23 June: grills on every pavement doing sardines and pork, garlic flowers held under strangers' noses, and above all the martelinhos - squeaky plastic hammers, sold by the thousand, which everybody uses to hit everybody else on the head, including tourists, police and grandmothers, without exception or offence. It replaced a leek used the same way. At midnight fireworks go off over the Douro from a barge below the Dom Luís bridge, watched from both banks; through the night paper hot-air balloons are released, which is technically restricted for fire risk and happens anyway. Bands play at Fontainhas, and by dawn people walk down to the sea at Foz to swim or watch the sun come up. Cascata altars of miniature scenes are set up in the old streets.

What you actually see

• The plastic hammers - the whole city hitting each other on the head, all night.
• The midnight fireworks - launched from a barge on the Douro below the bridge.
• The pavement grills - sardines and pork cooked outside every doorway.
• The dawn at Foz - the walk down to the sea as the night ends.

When to go

The night of 23 into 24 June, every year. A full night, ten in the evening until sunrise. Book accommodation months ahead.

Honest expectations

Crowds are enormous and movement through the Ribeira becomes impossible at times. Heavy drinking everywhere. Public transport runs but is overwhelmed. The hammers are constant and unavoidable - if being hit repeatedly by strangers would bother you, this is not your night.

Nearby

The Ribeira and the bridge are the centre; Foz is where the night ends.