To find Crime Alley, head south from the Church. The alley itself is just above the letters “Restricted Area” on your map. If you’re travelling around, you might find the Monarch Theater. Head around back of the theater.
In the alley, look for a lit section of concrete where two fresh chalk outlines have been drawn. Some flowers are laid down, with a note from Hugo Strange, and a tape.
Stand near the red rose and interact to kneel at the site of Batman’s parents’ murder. Don’t move for a minute, and you’ll unlock the achievement / trophy.
Be sure to take the tape left by Hugo Strange before you leave.