Her flared iron, however, showed her something else. She frowned, continuing forward until she reached a stationary source of metal—two small bronze bars stuck into the ground a couple feet from each other. She flipped one up into her hand, then looked into the swirling mists to the north.

He’s jumping, she thought. But why? Jumping was faster than walking, but there didn’t seem much point to it in the empty wilderness.

Unless…

She walked forward, and she soon found two more bronze bars embedded in the earth. Vin glanced backward. It was hard to tell in the night, but it seemed that the four bars made a line that pointed directly toward Luthadel.

So that’s how he does it, she thought. Kelsier had an uncanny ability to move between Luthadel and Fellise with remarkable speed. She’d assumed that he was using horses, but it appeared that there was a better way. He—or perhaps someone before him—had laid down an Allomantic road between the two cities.

[...]

[Vin] got the hang of it quickly, hopping from point to point, never dropping even close to the ground. In just a few minutes, she had the rhythm down so well that she barely had to do any corrections from the sides.

Her progress across the scraggly landscape was incredibly swift. The mists blew by, her mistcloak whipping and flapping behind her. Still, she forced herself to speed up. She’d spent too long studying the bronze bars. She had to catch up to Kelsier; otherwise she’d arrive in Luthadel, but not know where to go from there.

She began to throw herself from point to point at an almost reckless speed, watching desperately for some sign of Allomantic motion. After about ten minutes of leaping, a line of blue finally appeared ahead of her—one pointing up, rather than down toward bars in the ground. She breathed in relief.

Then a second line appeared, and a third.

Vin frowned, letting herself drop to the ground with a muted thump. She flared tin, and a massive shadow appeared in the night before her, its top sparkling with balls of light.

The city wall, she thought with amazement. So soon? I made the trip twice as fast as a man on horseback!