At the seafront boulevard near the Vischpoort is the sightseeing train "station".
The train itself is called the Boulevard Express.
The sightseeing trains run from 1PM to 6PM
From 10AM - 12AM the train runs from the Harderwijk train station to the Boulevard.
After 4PM it also runs from the Boulevard to the local car parks and the Harderwijk train station.
Sightseeing train ticket: € 3,50.
No service in the winter season.
Of course, the most ideal way to come to Harderwijk is to sail your boat from the Veluwe-lake into the harbour and start exploring. However, most people come by their own car or by touringcar (as many organised trips to the Dolfinarium can bring you to this town). There's also a trainstation that is approximately on the middle of the trachs from Utrecht / Amersfoort and Zwolle.
We went there by car and it was easy to get there. Just take route A28 (Amersfoort - Zwolle) and follow the "Dolfinarium" signs all the way.
If you come by rail, just take the train to Harderwijk station.