My experience in checking alignments leads me to the conclusion that the ancients or the advanced beings in charge use ideal conditions and not topical morphological characteristics like hills. In other words we need to use a zero altitude ideal horizon - just like the one you can inspect using astronomy software like Starry Night. Now in regards to New York July 13, 2013 wiki says: "Half sun". On this date the Sun passes the ideal horizon at an azimuth that aligns to the New York grid - azimuth 299 degrees. The true Alexander birth date has shifted 8 days, from July 21 to July 13.