The split boulder forms a gun sight-type “V” that points accurately at the vertical, lower edge of the sea-cliff 330-feet away (100 metres), at an angle approaching 59.5-60 degrees azimuth.
From the beach viewing position, one visually aligns the base of the split-apple “V” with the vertical edge of the cliff to form an accurate alignment onto the winter solstice, first-glint sunrise position. The sun, rising on a slight diagonal to the left (North), then climbs the edge of the cliff to launch itself into the sky from the cliff top. From the position of observation at beach level the sea horizon conjuncts perfectly with the base of the “V” and first-glint of the sun occurs low in the “V”.
The winter solstice sun climbing the cliff edge. The first-glint position seen at the base of the “V” represents the most northerly position the rising sun will move to in its annual journey up and down the eastern sea horizon and distant land-masses.

SPLIT-APPLE ROCK ALSO WORKS PERFECTLY FOR DETERMINING THE                                                              EQUINOX SUNRISES
Whereas the sun rises at 59.5-60 degrees azimuth at the time of the Winter Solstice, at the Autumnal (March 21st) and Vernal (September 21st) equinoxes it rises at 90-degrees. To accurately witness the two annual equinox events through the Split-Apple "V" one moves to a more westerly position of the beach. By viewing through the "V" to ranges across the sea situated at 90-degrees azimuth, the exact day of the equinox can be accurately fixed.
At this point of the beach viewing position the "V" in Split-Apple Rock is half diminished in depth, but still highly visible and exploitable for cradling the equinoctial sun's orb. In the much magnified background is seen the distant range across the water, where the sun rises from a peak 1800-feet high (550 metres).

The equinoctial sun cradled in the base of the "V" after rising from behind the distant range. It then moves upwards into the morning sky on a slight diagonal to the north.
It is very apparent that Split-Apple Rock works perfectly as a solar observatory for both the winter Solstice and equinoxes. It would also work fine for the summer solstice sunrise (120-degrees) fix as well, although the "V" would be much diminished and represented only by a small trough in the crown of the boulder, as seen from the observer's position on the beach.

THE SUPERMOON RISE AT THE EQUINOX

On the occasion of the 2019 autumn equinox for the Southern Hemisphere a super moon rose almost exactly on the equinox line. This was a rare event not to be missed.
On the evening of the equinox the super moon rose through the "V" of the Split-Apple very close to the solar equinox rise position and is seen here cradled in the "V".
This extreme northern position along the shoreline is where one would need to be in order to observe the summer solstice for the Southern Hemisphere, using Split-Apple Rock as the outer marker. The "V" aspect of the boulder is much-diminished to only a concave trough, but would be sufficient for a finite fix on the sunrise. Alternatively, the right-hand base of the boulder could be used to capture "first-glint" of the sun on the horizon, followed by its diagonal climb up the edge of the boulder to the trough position.
On this line of sight, just above the beach, is a wide assembly flat-area where ancient people could once have gathered for their summer solstice festivities. That expansive piece of terrain has not been subjected to modern-day machine modifications, as there would be no access due to steep hills behind.​