I visited Hämeenlinna where I was born. It has quite many sightseeing places worth checking out. Hämeenlinna is located between Helsinki and Tampere by the lake.
The Castle is obvious, but there is also other not so well known places. In this trip I did not visit Aulanko as I had reserved only one afternoon to wander around the city. Plus I have been mountain biking at Aulanko all my youth so know it already quite well..