Note: Before Nagasaki, we stopped in Busan, Korea but it was really not that great of a shore excursion.
We took the Nagasaki walking tour which was great. It showed us how to get around Nagasaki on our own using their trolley/bus system. The Peace Park was very tranquil...with the Peace Memorial on one end and the monument where the detonation took place on the other end.
Read Duane T's full Diamond Princess cruise review