Saint Demetrios is the patron saint of Thessaloniki, a Roman soldier martyred in the early fourth century, and his church is the heart of the city's religious life. The basilica stands on the hill above the old Roman forum, on the site where Demetrios is said to have been imprisoned and killed, and over the centuries it was rebuilt several times after fires. The present church, a great five-aisled basilica of the seventh century, was devastated by the fire of 1917, which destroyed much of the city, and was rebuilt in the following decades. A few of the early mosaics survived, set in pillars and walls, showing the saint with children and officials, and they are among the most moving works of the period.
Beneath the church there is a crypt, a series of vaulted chambers in the ruins of a Roman bath, where tradition places the saint's prison. It is cool, dim and quiet, and a small museum holds fragments of sculpture and tombs. Demetrios is also the protector of the city in battle and plague, and in the stories he turned up on the walls to repel attackers, including the Slavs in the seventh century. The feast day in late October is celebrated with processions and a fair, and the church fills with candles.
Thessaloniki's roads are a challenge, since it is the second city of Greece, with roughly a million people in the metropolitan area. The traffic is dense, drivers are impatient and scooters weave through every gap. The streets around the church are one-way, and parking is scarce, though motorbikes are usually tolerated on the pavement edges, and the district is a short walk from Aristotelous Square and the sea front. Tram tracks are not an issue here, but the surface can be slippery with polished stone and wet leaves. Go on a weekday morning to avoid the worst of the traffic.
Fuel is plentiful on the ring roads and avenues, and food is excellent: a plate of grilled sardines, a sweet trigona pastry filled with custard, or a bowl of hearty bean soup will cure fatigue. The nearby streets are full of cafes where the old men play backgammon, and the market quarters offer cheap and cheerful snacks. Visit in spring or autumn and give yourself time inside the crypt. Dress modestly for the church and do not photograph the faithful while they pray.