Cortana: "Don't let them lock the doors!".
A group of Covenant stand guard at the door, with a Sangheili Zealot blocking the way in. The Chief enters the structure and reaches the top of a slope that leads to an open door. My analysis indicates that the map room should be at the bottom floor of this facility.
Cortana: "The Covenant are putting up a real fight! The Cartographer must be here.They eliminate the patrolling troops outside the structure. Marine: "Anyone else see what I see? How are we supposed to get around that, huh?".Cortana: "They're already inside! We need to get in there quick, before they discover the location of Halo's control center!".Cortana: "There, in the cliff wall I'll bet the Silent Cartographer is somewhere inside that facility.".The vehicle approaches a structure protruding out of the cliff wall. The Warthog proceeds to drive off around the island, encountering Covenant resistance. Let's go find the map room that will show us the location of Halo's control center."