Open the History Manager <Control> (Mac=<Command>) <Shift> H. In the search bar, enter the name of the site.

Note: Only the latest access is shown in the manager.

Thanks a lot Fred but that didn't give me what I'm looking for. I need to prove that I accessed a site on a specific date (1st Nov) and the time I did so. Any further ideas will be much appreciated. Cheers, Patrick

I agree with what Fred said and it shows the time I visited the site. screenshots

I think there is an add-on that can help. But I don't remember its name.