Waterfall, by Lisa T. Bergren, is the fist book in the River Of Time series. There are 5 books, plus some novellas. Gabriella is 17 and spending her summer at yet another dig, this time in Italy. Her mom is an archaeologist, and so was her Dad, before he died. I loved the feel of the beginning of this book, to me it was very Indiana Jones-esque. Some things happen (I don't want to give it away) and Gabriella and her sister, Evangelia, time travel to medieval times, and they get separated!
This book is really good at talking about the politics going on in Italy at the time that the girls go to. I know some about this time period, but this book really made me think about it more. I really loved Gabriella's devotion to finding/getting back with her sister; it was a lot like how I think I would feel in her situation, and as an older sister.
Now, on to the romance. I felt that the romance was believable, but I wasn't really rooting for them. I think that this is because I was VERY spoiled about their relationship. But I do really like them as a book couple.
In this book there were plot twists that I saw coming, and there were some that made me guess if someone was going to live or not! I was expecting different things in the way of how this book was Christian, but I like how the story is unfolding and laying the pieces out for the next books. I loved that the characters felt very real, and that Gabriella was not stereotypical to most girls in stories where there is time travel. I also enjoyed that she did a lot of things that I think I would have done in her place.
I would recommend Waterfall for ages 13 +, because there is a lot of violence, and a bit of kissing, and things like the political aspect that I think anyone younger would not care for.