the trenches are on either side. The Italians have a 1 square deep trench on the left, and the Austrians have a 3 square deep trench on the right. This is indicated by a dashed line. The two A squares are where Artillery is placed, and the A6^, A5^ and A4^ are on the board to indicate Artillery fire zones. These are between the trenches, and separated by red lines. To hit with Artillery, you need to roll a D6 at the number listed in the zone or above, so close to the Italian trench, the austrian Artillery hits on a 6 or up. Near their own trench they hit on a 4 or up.

Hope that clears things up, and thanks for downloading!