Given the importance of this data, it's not surprising that researchers would go to great lengths to obtain samples of ancient glacial ice. The first step in obtaining good ice core samples is to identify a useful drilling site. We're looking for a very specific area. Scientists look for either a flat area of the glacier or a dome-shaped area. Domes are nice because ice at the center of a dome is generally being stretched equally in all directions.
Glaciers do the same thing.
After a potential drilling site is located, planes with ice-penetrating radar are flown over the site to map the underlying ground. A camp that can shelter 40-60 people is then set up on the site so that work can proceed during the 3 months of Antarctic summer. The drilling crew works 24 hours a day. Working late isn't difficult since the sun never sets. The deeper the hole gets, the longer it takes to retrieve a section of core.