Outlander (Outlander #1) by Diana Gabaldon
It is 1946 and Claire Randall, a British Army nurse returns to her husband after working as a nurse during the second world war. To start a new life, Claire and her husband, who is a history professor decide to depart for their second honeymoon to Inverness, Scotland.
Frank begins to conduct research about his family and for Claire, she suddenly enters into an ancient circle where she becomes and Outlander “Sassenach”.
In that land, she is hurled back in time with unknown people surrounding her. She is taken into custody, but with time, the community begins appreciating her medical skills. Claire is believed to be a spy in that land, but yet, she seeks a way back to her normal life.