The walk according to view ranger came in at 14.11 miles, and started at the Great Western Beach in Newquay and ended at the Watering Hole on Perranporth beach. Its a great walk and had so many great little moments. The Ferry ride over the Gannel, the views from the Cliff tops, Porth Joke beach and a ice cold drink at Perranporth. Crantock, Holywell Bay and Perranporth are all great beaches.
The Coastal buses make it easy to do logistically too.
A video of the walk is here -
https://youtu.be/gg6iGszWzQI