Razors — Palos Verdes surf break

Spot names and descriptions were extracted from the PDF text layer.

The red arrows were isolated from the chart rasters by colour, and each arrowhead located.

Each chart's waterline was traced and registered against the present-day OpenStreetMap coastline, giving a transform from chart pixels to latitude/longitude.

Every arrowhead was pushed through that transform.

Figure 2 is drawn at roughly half the scale of Figure 1, and its arrowheads land much further out to sea — a median 246 m against 78 m. South-side pins are therefore pulled in toward the shore by a factor of 0.32, so both halves of the map sit at the same median distance from the beach. Scaling rather than subtracting a fixed distance keeps the spacing the author drew and never crowds a pin onto the beach. The untouched arrowhead position is kept alongside each spot.

A very small number of pins are corrected by hand where local knowledge beats the 2003 arrow — currently one, Wallies Left, which the chart places outside and north of Wallies when it is in fact inside the cove and south of it. Those cards say so.