The pictures on that site--including my favorite here, which belongs to Livius & is © Marco Prins and Jona Lendering--are of the Selle River. As I understand it, other locations have their adherants, and no discoveries have settled the matter. No battlefield remnants have been found, IOW. I think the Escault River is another possible site.
Still, these pictures are great, very well researched, and fit all that is known about the Sabis River site. Except . . .
. . . well, the picture right above is, according to the site, a hill called Le Quesnoy, and the spot where Caesar's 10th Legion had parked. A hill? Seriously? The "slope" to the right leads down to the river.
Here is what Caesar says, according to my copy of The Conquest of Gaul:
"2:18 At the place that the Romans had chosen for their camp a hill sloped down evenly from its summit to the Sambre. Opposite it, on the other side of the river, rose another hill with a similar gradient, on the lower slope of which were three hundred yards of open ground. . ."
Sambre was the Roman's name for the river.
The Livius site says this last picture looks from the Nervian side of the river, looking toward where the 12th and 7th legions of Rome assembled. Here, yes, I do see a hill. However, most of the landscape in the pictures (and there are over a dozen) show land I consider pretty flat.
In fact, I will throw in the small version of a last picture, showing the Nervian campsite. Remember, this is supposed to be a similar hill, with 300 yards of open ground on its lower slope.
I guess the jury's still out.