Xi Chin rises from a high plateau in the central Tethryn Mountains, its white marble stark against the dark volcanic stone of the peaks. From a distance it seems to glow at dawn and dusk, the marble holding the light after the surrounding mountains have fallen into shadow. On a clear day the towers are visible from ships out in the Gulf of Xoth. What those ships cannot see is what the marble was built around.
The buried sphere
Lodged in the mountain beneath the city, driven in like a coin pushed edgewise into soft wood, is a sphere. It is metal, or something close enough to metal that no smith has named it, and it is vast, larger than the city grown over it. A Mira orb-ship fell out of the sky into this peak ages ago, and there it stopped. The first builders did not so much raise Xi Chin on the mountain as fit it into the wreck, setting marble halls against the curve of the hull and quarrying the volcanic rock the impact had thrown up around it. Most of the sphere lies buried. The part that matters is the top.
The Eye, the city calls it: a long tear in the crown of the buried sphere, wide as a market square, where the metal split on impact and never closed over. Rain falls through it. Snow falls through it. At noon a hard column of light drops the length of the shaft and lands on the floor of the Great Clocktower, and by where it falls the Chroniclers read the day.
Staying
The danger of Xi Chin is not the climb. It is the staying. Anyone who comes up the Wister Road and spends a few days inside the city begins to feel the sphere's aura, a low pull at the back of the mind, a reluctance to be anywhere else. The reluctance hardens fast. By the end of a week most visitors find they cannot make themselves leave at all, and by then leaving would kill them. A body that has lived in the aura past the fourth or fifth day dies on the descent, somewhere below the second switchback, for reasons no physician has learned to undo. Pilgrims and envoys who mean to go home again keep a strict count of their days and leave while the count still lets them. Some misjudge it. The graves along the upper Wister Road belong mostly to people who stayed one morning too long.
So the city has filled, over the ages, with people who came for a reason and then could not leave. Traders, scholars, refugees, the merely curious, pulled in from every coast the Wister Road touches and then cut off from homes they could never return to. They fused. Xi Chin speaks its own compound tongue, keeps festivals no outside calendar marks, and traces its families through humans, dwarves, gnomes, and others who have not lived apart for a hundred generations. Over all of it preside the Mira, whose fallen sphere makes the place what it is and whose three rigid castes set the shape of its order. The Mira do not count themselves trapped. They count themselves home.
The Timekeepers
The Eye made astronomers of them. Given a fixed window onto the sky and nothing but time, the people of Xi Chin took to measuring it, and the precision they reached over centuries is the reason the rest of the Greenwater Isles set their clocks by them. The Great Clocktower stands directly under the aperture, its movement driven and corrected each day by the column of light that crosses its floor. Out in Wister Valley the standing stones, older than the city itself, mark star-rises the Chroniclers still use for their most exact work. This is the strange power of the place: a city that cannot defend itself, full of people who cannot leave, that the courts and congregations of the Isles cannot do without.
That power rests on the Chroniclers' Compact, the old agreement by which Xi Chin takes no side in any war and sells its reckoning to all sides at the same price. A city of hostages has little use for armies and less for allies, and the Chroniclers have made both a virtue and a living out of staying out of everyone's quarrels.
"You are met at the gate by a child who asks the day of your arrival, and met again each morning by that same child, who tells you how many you have left. On the fourth morning she does not smile. Cross her on the fifth and she has already stopped counting you among the living." — from a Harborflame envoy's notes on the embassy to Xi Chin