Hollandia was the principal Japanese rear supply base in New Guinea. A sheltered but undeveloped harbor located on Humboldt Bay, it provided the only protected anchorage of any size between Wewak and Geelvink Bay. The airfield area, shielded from the sea by the high Cyclops mountain range, was near Lake Sentani, about twelve miles from Humboldt Bay and midway to Tanahmerah Bay to the west. The bulk of the enemy's remaining New Guinea air strength was based on three large airdromes in this area. Hollandia also served the Japanese as a important trans-shipment point for the unloading and transfer of personnel and cargo from large transports to smaller coastal vessels. A considerable backlog of supplies was observed on the beaches and in the vicinity of the airfields. Intelligence estimated the number of Japanese troops in the Hollandia-Aitape area at the end of March to be 15,000; at Wewak-Hansa Bay, 30,000; at Wakde-Sarmi, 5,500; and in the Manokwari-Geelvink Bay area, 11,000. A large Allied task force was gathered in expectation of a difficult campaign. The closest teamwork of all participating components would be required to accomplish the largest operation and the longest amphibious move yet attempted in the Southwest Pacific Area. The projected operation involved a distance of 985 miles from Goodenough Island, the principal staging area, and over 480 miles from Cape Cretin, south of Finschhafen, the advance staging point.
General Krueger, Commanding General of Alamo Force, was made responsible for the co-ordination and planning of the ground, air, and naval forces. General Eichelberger, commanded the main landing group comprising the 24th and 41st Divisions, which was to seize the Hollandia airdromes by invasions at Humboldt Bay and Tanahmerah Bay. Brig. Gen. Jens Doe, commanded the 163rd Regimental Combat Team which was to land in the Aitape-Tadji area and capture the Tadji airfield. Another combat team would be kept in reserve. The naval forces were to provide air cover and escort protection. Admiral Barbey was in charge of the naval amphibious forces while the carrier forces of the Fifth Fleet were under Rear Adm. Marc A. Mitscher.
The entire task force for the invasion rendezvoused north of the Admiralties and then proceeded in a northwesterly direction toward Palau. Although this course was 200 miles longer than the direct route, it was intended to mislead the Japanese and prevent them from determining the exact objective in case of discovery by aerial reconnaissance. Swinging suddenly southward the huge convoy approached the New Guinea coast. On 21 April, fast carrier planes struck the Wakde-Sarmi, and Hollandia airfields while the Fifth and Thirteenth Air Forces concentrated on Wewak and Hansa Bay.
On 22 April, after heavy preliminary naval and air bombardment, the invasion troops went ashore according to plan. Complete tactical and strategic surprise was achieved.
The convoys had sailed within striking distance of their objectives apparently without detection. The ease of the landings exceeded even the most sanguine hopes. No more than token resistance was met at any point and there was no interference from the enemy's air or naval forces. The painstaking deception measures had been remarkably effective.
In the Hollandia area, United States troops made a virtually unopposed advance. At both Humboldt Bay and Tanahmerah Bay opposition to the landings was ineffective and the two jaws of the giant invasion pincers clamped down rapidly on both sides of Mt. Cyclops. So stunned was the enemy by the unexpected landings, that in the beach area complete radar sets and other valuable equipment, still uncrated, were left behind to be captured. Progress was limited only by the problems of supply and the difficult terrain since the Japanese had failed to exploit the natural defensive positions offered by the narrow mountain defiles. On 26 April the Sentani, Cyclops and Hollandia airdromes were captured. In the meantime the Tami airstrip, lying on the coastal flat east of Humboldt Bay, was secured. With all objectives achieved, only mopping up operations and consolidation remained for the combat troops. On 6 June the Hollandia phase of the operation was officially closed.
1, 2 & 3 were taken of the crowded beach. You can see our Mobile Labs sitting idle. There was only one road off that beach which was only 50 yards wide and backed up to a swampy area. In the 2 weeks since the initial landing the Japanese had bombed the beach 3 times and we were sitting there among 500 lb. bombs and 90mm Artillery shells. 4 & 5 show us just killing time. 6 is of our cook trying make sure we had chow. 7 & 8 show Seeley & Anderson working with an 8 x 10 View Camera.