Metal Gear (NES)/Path to Building 1
A1: From the start, you will arrive at the entrance of a jungle north of the first building. Big Boss will contact you on the transceiver. He will give you the mission instructions: infiltrate Outer Heaven, locate Gray Fox, and destroy Metal Gear. He will tell you to contact him on frequency 120.85. Then proceed east to A2.
A2: Once soldier stands guard to the right of a car. He is tired and will likely fall asleep shortly after you arrive. This will allow you to walk up to the soldier and knock him out by punching him three times. Walk south to B2.
B2: Three dogs lay dozing on the ground amongst the vehicles. As you make your way through here, the dogs will wake up and begin chasing you through the screen. You can stop and punch them three times to knock them out, or you can ignore them altogether. Proceed south along the right path to C2.
C2: A dog is asleep along the right path. Assuming you are on the right, you can choose to stop and fight it, or leave it alone. Either way, make your way south to D2.
D2: You will encounter the first (wide awake) soldier here guarding a truck. You can try to sneak up on the soldier and knock him out with punches, and then investigate the truck by approaching the right side. Inside the truck, you will find the binoculars, which allow you to preview the four screens on either side of you. When you exit the truck, the soldier will return. While it's possible to sneak up on the soldier before you enter the truck, it is impossible to escape without detection. The best way to avoid the first shot that he fires is to move down as soon as you exit the truck. Fight with or flee from the soldier and continue south to E2.
E2: Two soldiers stand guard along the path. They remain motionless, but they do turn around to look in four directions. Time your approach to each soldier so that they are facing away from you when you reach them. Punch each one out and continue south to F2.
F2: A dog sleeps in the middle of two crossing paths. Although you can explore the path to the left or right, it will simply lead you back to the opposite side of the same screen. No matter how many times you move left or right, it will not make any difference to your progress or position with respect to the first building. Continue south to G2.
G2: Two soldiers stand guard on either side of the small booth. While you can go either way around the booth, the left soldier is a little more accessible to attack. Knock out the left soldier, ignore the right soldier, and continue south to H2.
H2: There are three trucks here, two of which are covered. Two soldiers stand guard among them. You can't examine the uncovered truck, but you can investigate the other two. The left covered truck contains access card 1, which you will need to enter the first building. The lower truck on the right is the next truck that you must visit, but you are likely to attract the attention of the soldiers after collecting the first card. Do your best to avoid attack while you fight or avoid them. Then hop inside the lower truck. When you do, it will begin to move. When it comes to rest, you will find yourself outside of Building 1.