The most extensive construction on
Corregidor was the tunnel system under Malinta Hill. Consisting of a
main east-west passage 1,400 feet long and 30 feet wide, the tunnel had
25 laterals, each about 400 feet long, branching out at regular
intervals from each side of the main passage. The underground hospital
was housed in a separate system of tunnels north of the main tunnel and
had 12 laterals of its own. It could be reached either through the main
tunnel or by a separate outside entrance on the north side of Malinta
Hill. Opposite the hospital, under the south side of Malinta, was the
Navy tunnel system, connected to the main tunnel by a partially
completed low passageway through the quartermaster storage lateral.
Reinforced with concrete walls, floors, and overhead arches, blowers to
furnish fresh air, and a double-track electric car line along the
east-west passage, the Malinta Tunnel furnished bombproof shelter for
the hospital, headquarters, and shops, as well as a vast labyrinthine
underground storehouse.
The armament of Corregidor was formidable.
Its seacoast defense alone consisted of 23 batteries, many with their
own names and traditions. Altogether, Corregidor had a total of 56
coastal guns and mortars, all of World War I vintage, ranging in caliber
from 3 to 12 inches. (Table 9) The longest range cannon
were the two 12-inch guns of Batteries Smith and Hearn, with a
horizontal range of 29,000 yards and all-around traverse. In addition,
there were six 12-inch guns with a range of 17,000 yards, and ten
mortars of the same caliber. Nineteen of Corregidor's guns were the
155-mm. GPF's, capable of a range of 17,000 yards. The ten 3-inchers had
the shortest range. The supply of seacoast ammunition was ample but
there was little of the type suitable for attacking land targets and no
star shells to provide illumination for night fire. North and south of
the island were extensive mine fields planted by the Army and Navy.
Antiaircraft equipment consisted of 3-
inch guns with a vertical range of 27,000 and 32,000 feet (depending on
the type of ammunition used), .50-caliber machine guns, and 60-inch
Sperry searchlights. Defending Corregidor from air attack were 24 of
these 3-inch guns, 48 machine guns and 5 searchlights. Another battery
of 3-inchers was emplaced on the southern tip of Bataan to tie in with
these on Corregidor. Ammunition for the antiaircraft weapons was less
plentiful than that for the seacoast guns, and there was a critical
shortage of mechanically fuzed 3-inch high explosive shells.
Before the war, the Corregidor garrison
consisted principally of headquarters, artillery, and service troops.
The combined strength of the four fortified islands in Manila Bay at
that time did not exceed 6,000 men, most of whom were stationed on
Corregidor. After 8 December the population of these garrisons swelled
rapidly. First came the survivors of the Cavite naval base, then the
headquarters and service troops from Manila. MacArthur's headquarters
was established on Corregidor on 25 December and with it came the 809th
Military Police Company, two ordnance companies, an engineer company,
and service detachments. When Olongapo was evacuated on 26 December, the
4th Marines were also transferred to Corregidor, swelling its population
by over 1,000 men. Before the first blow hit that island, it was already
crowded with the men of all services and a dizzying pyramid of
headquarters.
a pariatur?