I'd thought this was the first volume of a trilogy of YA time-travel novels; when it arrived, I discovered it was the third. Damn. Earlier vols are now on order from my long-suffering library . . .

After a collapse of civilization because of climate change, a gentle tribe makes their way from fiery southern zones to settle in what was once the west of Scotland. Now, in AD2179, the girl Lara Avara must establish herself in a world newly rent by an invasion of the Barbaric Ones, who carry much of the tribe -- Lara Avara not included -- off to slavery somewhere further south on the British mainland. The tribe has long held a nearby stone circle in reverence; and it proves that, buried underground where it looks as if there are stones missing from the ring, there are menhirs that have the special property, when handled by sensitives, of opening up time portals -- either for viewing or even for travel. Through such a portal into Lara Avara's time come a pair of 20th-century children, Jennifer and Robert, who bring their own further complications to the future world. All is eventually resolved, of course.

This is a very nicely written book, and I much enjoyed reading it. (I was puzzled, though, by how Robert's and Jennifer's speech was instantly comprehensible by the 22nd-century folk while the speech of the Barbaric Ones was just so much gibberish to them. Surely the two modern dialects would have been closer to each other than to one separated from them by a gulf of 200 years?)

No real mechanism for time travel is offered beyond that it's Yer Mystic. However, there's an interesting notion which, although eventually it's cast aside, shouldn't go unmentioned. Robert is a farmer's son, and his dad is making him follow in the family profession even though the youth really wants to be a painter, and is good at it. A solution to his dilemma is offered: one Robert could remain here in the future, complete with artistic ability and zeal; while another could exist in the 20th century stripped of all painterly yearnings. I can't remember having come across this idea before -- that time travel could be used to allow individuals to fulfil two separate life-plans, as it were. As I say, Anderson discards the concept soon enough, possibly because it'd have brought unwanted complications into her tale; the right decision, but on the other hand a pity.

I'm looking forward to reading the other titles in the series.
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