A forum member asked me if it was a single shot or a combination of multiple shots.
It was a single photo. I actually have a bracketed sequence, but decided to use just one of the three, the one that was most underexposed. The reason being that, at such a low light level, the exposure for the other two, the normally exposed and +1, was too slow, so the boat is not sharp, and I even had a camera shake in the +1. The price to pay for using the underexposed one is the noise in the shadows, but it is amazing how good the software - LR - is these days (four years after I took the shot).
If I decide to print it big, however, I might try combining it with the normally exposed shot, for better details in the buildings.