Mauna Kea is sacred to the Native Hawaiians and very important for researchers. In Hawaiian culture an ancient law allowed only high-ranking aliʻi to visit its peaks. By 1964, thirteen telescopes funded by eleven countries have been constructed at the summit. Currently, the Mauna Kea Observatories are used for scientific research across the electromagnetic spectrum and comprise the largest such facility in the world. Their construction on a landscape considered sacred by Native Hawaiians continues to be a topic of debate.