Hiking to all 3 shrines in one day

Is it possible to hike from Kumano Hongu Taisha to Hayatama Taisha to Nachi Taisha all in one day? I know I'd have to start the day early if I had any chance.

No, it is not really possible to hike to all of them in a day if you actually want to see and enjoy the experience.

According to Google, the hike would take 12 hours 18 minutes. Google does use roads rather than the Kumano Kodo walking route however, the walking route is not likely to shorten the trip.

Here is the Google link to the route:
https://www.google.co.jp/maps/dir/%E7%86%8A%E9%87%8E%E6%9C%AC%E5%AE%AE...