Search - Eyes of the Calculor

this entire series is fabulous (Souls in the Great Machine, The Miocene Arrow, Eyes of the Calculor). try to read in that order, but it's not absolutely necessary. Futuristic world where technology has to be re-invented, and the countries that are left are struggling with computers (the Great Machine, the Calculor), air travel, vehicle power, etc. while some areas are plagued by "the call" which causes people and animals to walk blindly toward the sea, if they don't tether themselves. Interesting characters with noble causes - but none of the silly, sappy sword/sorcery nonsense.

McMullen provides an interesting read - recommend reading him all.