Holy crap, they look imposing! How big are they actually?

These are actually small pieces that have calved off the 'mother ship,' a huge tabular berg. We later saw on a satellite image that this huge berg, that had been on the horizon for most of one day as we sailed past, was half the length of South Georgia, around 50 miles long! This was part of the Larsen B Ice Shelf that had broken free a year or so earlier. We estimated around 50m of ice above water.

Looks to be soe good lines on those