Chios

Chios has a second harbour in the southwest near Mesta. It handles small local traffic; scheduled ferries and the Turkish crossings all use Chora.

Mention it only because search results sometimes list it and it is on the opposite side of a large island. Unless your ticket says otherwise, you are arriving at Chora.

Look at where the sailings actually concentrate and the picture is not about Turkey at all:

• Lesvos — 11 sailings southbound and 8 northbound, about 2 h 20 m, on Blue Star and Hellenic Seaways. This is the busiest link the island has.
• Piraeus — 7 sailings, roughly 7 h 25 m.
• Samos — 3 sailings, about 3 hours south.

Chios is the middle link in the North Aegean chain rather than a terminus, which is why it has more sailings to Lesvos than to anywhere else including Athens.

The south of the island is the only place in the world where the mastic tree yields usable resin. It has shaped the place for centuries: the fortified villages of the mastichochoria were built to protect the crop, and the trade financed them.

Pyrgi is covered in geometric black-and-white xysta plasterwork and has the mastic museum nearby. Mesta is a medieval labyrinth built as a single enclosed castle-village against pirate raids — the outer houses form the wall, with no street visible from the sea.

Seven sailings a week to Athens and eleven to Lesvos is the shape of a place where people commute, ship goods and go to hospital — not a place built for a fortnight in August. That has consequences you can plan around.

Ferries keep running out of season. Prices are less peaked. Accommodation is available in July. And the island does not empty in October, because the people on it live there.

The main port is on the town waterfront, so arrival means walking off into Chios town rather than into a transfer. Ticket agencies, cafés and the bus terminal are on the same stretch.

The mastic villages are in the south, an hour or so away by road. Buses run but not frequently enough to build a day around; this is an island where hiring a car changes what you can see.

With 19 sailings between them across both directions, Chios and Lesvos are effectively one itinerary. The crossing is a little over two hours and runs frequently enough that you do not need to commit to which island you sleep on before you arrive.

Add Samos to the south and the North Aegean becomes a linear route with a Turkish crossing at each end — Çeşme here, Kuşadası there.

Piraeus and Lesvos sailings run all year. The Çeşme crossing is busiest from spring to autumn but operates outside summer too, unlike several other Greek–Turkish links.

The mastic harvest runs from roughly July to October and the villages are at their most alive then, which is also when the resin is actually being collected rather than merely sold.