Becca, I just checked your Stonehenge Hubs, and you did Grouping correctly. Go to one of the Stonehenge Hubs, and look at the bottom between where people rate your hubs and comment on them. You will now see links to the two Stonehenge Hubs that are grouped directly next to the one the reader is reading, which the reader can now click to go directly to those hubs, which also have the two Stonehenge Hubs that are grouped directly next to the one the reader is reading, etc.
The way Hubs are listed on your profile is controlled by what Category you placed the Hubs in and is separate from Grouping. To have them all appear in the same area of your profiles, put them in the same category, such as History and Archaeology.