Elven caravan came. The elves made it inside, just as a goblin siege started. I activated the military, manned the bastions with marksdwarves, and positioned the melee dwarves in the trade depot. Once the elves were safe, I raised the bridge, and sealed off the fort.
Some notes:
1. The goblins went after my animals in pasture outside the fortress. This was good, in that it brought them within bolt range from my squads, but it was costly for the animals.
2. The goblins still refuse to use my lovely trap-lined tunnel, preferring to ford the river where it is shallower.
3. It took a while, but the marksdwarves alone were able to defeat the goblins. The melee dwarves were sent out to finish off the survivors only. It does not make sense to me to put the melee dwarves at risk.
4. The animals may have run from the pastures when they were attacked. Is that normal?
5. One of my melee dwarves died before the start of the siege. I have no idea how or why. May have been wounded and died in hospital.
6. There appeared to be a single dwarf that hung out in the front, during the siege. Turned out to be a ghost.
So after all of that, I was looking forward to trading with the elves to restock my animals. They had a cougar and a grizzly bear. Unfortunately, I somehow offered them a wood product. I have no idea what or where, so they left in a huff. Regrettably, the goblins were all gone, so there was no chance to send them into the teeth of the siege.
In other news, I am starting the next level down from my great hall. It cannot be as wide as I hoped, since it turns out the magma sea is too close.