Star's Reach — John Michael Greer

More than four centuries have passed since industrial civilization stumbled to its ruin under the self-inflicted blows of climate change and resource depletion. Now, in the ruins of a deserted city, a young man mining metal risks his life to win a priceless clue. That discovery will send him and an unlikely band of seekers on a quest for a place out of legend where human beings might once have communicated with distant worlds - a place called Star's Reach.