The Town & Castle Tour c 1900 - possibly at Chepstow

I found this faded yellow print while tidying my desk and improved the contrast and removed the sepia tint.. It probably came from the Pritchard family's photo collection. There is no indication where it was taken. From the dresses and hats I estimate the date to be in the first decade of the 20th century.
The sign on the left says 'The Town & Castle' Tour'. The one on the building may say Restaurant. The gangplank seems to be resting on a pontoon at the lower end, making me think that this is the beginning of a steamer trip. One should be able to work out where this was taken if one looks for a town with a castle near a river or on the coast. There is a bridge at high level in the background which would suggest that this landing place was on a river, but that could still be near the sea. Although living in the Hereford area the Pritchards travelled extensively in the south-west and south Wales, with occasionally trips further afield.
One possible location might be Chepstow, a town with a castle and Brunel's tubular railway bridge. The bridge has a section which looks similar to the one in the background. It can be seen in the distance in this photo www.ipernity.com/doc/philsutters/26108863/in/group/1121191 If this is that bridge then this photo will have been taken from the far side of it.