Built by Hawaiian chiefs and kings as temples to the gods, heiaus are lava or limestone enclosures that once contained prayer towers, taboo houses, drum houses, and altars.
But heiaus have also proven vulnerable to centuries of neglect, and preserving and restoring them has not been easy.
Sinoto often has this inspirational effect on others - for no one has done more to preserve Hawaii's heiaus than the Japanese archaeologist.
In 1967, after identifying and restoring dozens of heiaus and other historic sites throughout Hawaii, Sinoto was asked by the government of French Polynesia to find and restore ancient marae - heiaus of the islands of Polynesia.
Thanks to Sinoto, dozens of heiaus and other archaeologically significant sites in the Polynesian triangle - the vast area of ocean and islands bounded by Hawaii, New Zealand, and Easter Island, with French Polynesia as the center - have been discovered and restored.
These are among Hawaii's most interesting and visitor-accessible heiaus.
The Hikinaakala (Rising of the Sun) Heiau is one of seven sacred heiaus at Wailua, Kauai's royal center.
Early risers can make their first stop a mile south of Kawaihae, at Puukohola Heiau National Historic Site.
Follow the road about 2 miles along a row of ironwood trees to a dirt road, turn left, then follow the washboard track another 2 miles to Mookini Heiau, one of the state's most important ancient religious sites.