If you join a full day tour in Hue, you will most likely end up at Tien Mu Pagoda as the last stop. This historical pagoda was built in 1601 by one of the first Nguyen Lords - Nguyen Hoang. Standing at seven stories high - it is the tallest religious building in Vietnam.
After the visit to Tien Mu Pagoda, you will most likely go on a boat trip back to Hue City. There are many of these Dragon Boats plying the Perfume River - mostly ferrying tourists. We were scammed by one of the boat ladies on our second day in Hue - she told us she would take us on a ride along the river for around RM50 - which we thought was a great due. It turned out to be a 10min trip crossing the river. Since it wasn't much money - we decided not to argue.
The best time for a boat ride would be in the evening when the sun is about to set. It is a nice feeling arriving at the City from the water.