On Tuesday 30 september 1941 or somewhere around this date, Einsatzcommando 3 murdered 366 Jewish men and 483 Jewish women. Also 597 Jewish children were killed. A total of 1446 persons died on this location in Trakai.
Source of this record: The so-called Jäger Report (full title: Complete tabulation of executions carried out in the Einsatzkommando 3 zone up to December 1, 1941) was written on 1 December 1941 by Karl Jäger, commander of Einsatzkommando 3 (EK 3), a killing unit of Einsatzgruppe A which was attached to Army Group North during the Operation Barbarossa. It is the most detailed and precise surviving chronicle of the activities of one individual Einsatzkommando, and a key record documenting the Holocaust in Lithuania as well as in Latvia and Belarus.
The photo is most probably not in this area but an example of German execution units and their work.