A total of 64 frames shot by the MAHLI on the end of Curiosity's robotic arm were required for this large mosaic. On sol 177 (February 3, 2013), the rover was sitting at the "John Klein" site, preparing to drill for the first time. Zoom in at lower left and you can see two gray marks on the ground where Curiosity tested out the drill in percussion mode on sols 174 and 176.
For a much larger (though still only half-resolution) version, click here (10 MB JPG).
Here's a closeup on the rover's "face."
On the same day, the rover also took a look under its belly: