Although common in other islands of Eastern Polynesia, cut-and-dressed masonry is exceedingly rare in Hawai'i. This article describes a significant exception, Kukuipahu Heiau, a monumental structure in the Kohala district, Hawai'i Island, which incorporates more than one hundred cut-and-dressed basalt slabs, as well as worked red scoria blocks. There appear to have been at least two construction phases, with an earlier phase utilizing the worked stone, followed by a destructive interval, and then a later phase characterized by more typical Hawaiian stacked stone construction. A precise survey of the structure shows that it deviates only slightly from cardinality, but when the altitude of the Kohala ridgeline is taken into account, the site was oriented within 1–2° of the equinoctial rising of the sun. Hawaiian oral traditions associate the hewing of temple stones with the famed Hawai'i Island king 'Umi-a-L īloa; we suggest that Kukuipahu Heiau may have been built during his reign, a hypothesis that deserves further research.