Well, I’ll say one thing about Fortress Sol — it’s not lacking in ambition.
In the 22nd century, a strange energy-based swarm consumes Neptune, and fearing this is a precursor to an alien attack, the human race takes a number of bizarre steps to defend itself, and ensure its survival if it can’t.
A generation starship is launched in a century-long journey to colonise a distant star system. …
… And much closer to home, an ambitious millennia-long project begins, to hide the solar system from the as-yet-unseen invaders.
A thousand years later, the Lightbird returns to the Sol system to see what has become of Earth. The crew finds that humanity has masked the entire solar system in a shroud, wrapped the Sun in a Dyson sphere, and is now travelling around the hidden solar system on a planet-spanning rail network!
As I said: ambitious!
The book is heavy on the detail and big on numbers. What impresses most is the sheer scale: everything is measured in astronomical units — which you’d need when talking about a rail network circling the solar system.
As far as the story goes, I found it somewhat lacking. The characters are fairly well- developed, with an interesting backstory for everyone involved. The prose is workable and even, though the pacing is quite slow in places. (We spend a lot of time on the rail network, travelling between planets). There were moments where I had the feeling I was reading the Lonely Planet Guide to Sol, rather than a book. Don’t get me wrong though; it was fascinating, even if it didn’t move the story forward much.
Fortress Sol is more of a project manifesto than a novel. It comes across as a discussion of how humanity might build megastructures in space — assuming that humanity has a thousand years left in which to do it. Unfortunately, I think the storytelling did suffer to some degree in order to make room for some of the deeper technical aspects .