The rope / Nevada Barr.

In this novel, the latest in the author's series of novels featuring Anna Pigeon, the author gathers together the many strings of Anna's past and finally reveals the story that her many fans have been long asking for. In 1995 and 35 years old, fresh off the bus from New York City and nursing a broken heart, Anna Pigeon takes a decidedly unglamorous job as a seasonal employee of the Glen Canyon National Recreational Area. On her day off, Anna goes hiking into the park never to return. Her co-workers think she's simply moved on; her cabin is cleaned out and her things gone. But Anna herself wakes up, trapped at the bottom of a dry natural well, naked, without supplies and no clear memory of how she found herself in this situation. As she slowly pieces together her memory, it soon becomes clear that some one has trapped her there, in an inescapable prison, and no one knows that she is even missing. Plunged into a landscape and a plot she is unfit and untrained to handle, Anna Pigeon must muster the courage, determination and will to live that she didn't even know she still possessed to survive, outwit and triumph.