The Haʻikū Stairs, also known as the Stairway to Heaven or Haʻikū Ladder, is a steep hiking trail on the island of Oʻahu, Hawaii.The total 3,922 steps span along Oahu's Ko'olau mountain range.
Beginning in 1942, contractors for the United States Navy began construction of the Haʻikū Radio Station, a top secret facility that was to be used to transmit radio signals to the Navy ships that were then operating throughout the Pacific. In order to obtain the necessary height for the antennae, the Navy stretched them across Haiku Valley, a natural amphitheater surrounded by high ridges. To accomplish this, they needed “easy” access to the top of the ridges, so they installed a wooden ladder up the mountain. The ladder was later replaced by a wooden staircase. (Those who had made the climb before the installation of the ladder referred to it as a “sissy climb.”) Once the cable car was in operation, most workers preferred to ride the car to the upper hoist house rather than enduring the tedious climb up the stairs. Some remnant parts of the wooden ladder may still be seen beside the metal steps. The radio station was commissioned in 1943. To transmit such a powerful signal, the Navy needed a transmitter of greater capability than was then possible with vacuum tube technology. They therefore decided upon an Alexanderson alternator, a huge device capable of generating powerful radio-frequency signals, and requiring an antenna of heroic proportions.