Cardiff to city center?

[mama2bifs]

My Mother (80 - but gets around well!) and I will be traveling via cruiseship to Cardiff in early September. We understand there is a lovely walking trail to the city center where we planned on catching the Hop on Hop off to visit the city and Cardiff Castle. We also want to go to Dyffryn Gardens. Does anyone know if that is also on the Hop on tour and if not is there a good way to get there or is it walking distance. Also, how long a walk are we anticipating from the cruise port to the nearest Hop on port (or city center in general)? I don't want to wear her out right off the bat!

Thanks!

[aquilegia]

Can't help with the walking trail, but Dyffryn Gardens are about 8 miles from Cardiff, and they're down quite a long lane from the main road. When I went there last year I went by car, but there might be buses. To be honest, while they were pleasant enough, I wasn't that impressed with them and I was disappointed that you can't go in the mansion.