Aerial photography from 1971 first revealed the full extent of these features: curvilinear earthworks running east and west of the castle, with additional rectilinear earthworks to the south. These grass-covered lines, still visible in satellite imagery from 2005, trace the boundaries of what was once a substantial bawn; a fortified courtyard that would have provided essential protection for this small castle built directly on exposed bedrock.

E.R. Dix documented these defensive features in remarkable detail during his 1897 visit, noting how the earthwork lines create a clear rectangular enclosure around the castle. Starting from the castle itself, the boundaries run northward before turning east for approximately 31 paces, then south for a considerable distance, west again, and finally north to rejoin the castle walls. In some places, these ancient boundaries still rise one or two feet above ground level, with large stones occasionally breaking through the turf. The eastern side of the castle shows traces of an adjoining building, whilst within the bawn itself, a partially circular stone-lined feature appears to be an old well, complemented by a natural spring just outside the fortified area.

This extensive defensive system suggests that Puck's Castle, despite its modest size, played an important role in the medieval landscape of south County Dublin. The combination of natural defences, including the rocky outcrop on which the castle sits, and these carefully constructed earthworks would have created multiple layers of security. The division of the bawn into separate sections, as suggested by the earthwork patterns, indicates a sophisticated approach to castle defence, possibly separating areas for livestock, storage, and residential use whilst maintaining the overall defensive integrity of the site.