Reaching the landing zone #2
1 - starting area
2 - destination
3 - observation points
4 - buildings guarded by Nanosuit soldiers
You can consider going towards the quarry before proceeding with the current mission objective. You would be able to take out a few soldiers from a higher ground. Obviously this is not necessary and you'll visit the quarry. As a result, you should go back to the southern gate and proceed with your main task.
Start moving towards the jungle. As a result, you will be heading south. You will come across a larger hill in just a second, so you must turn west. Don't worry, because you're still heading towards your current target. There aren't any enemies in this section of the jungle, so you won't have to use camouflage.
You should be able to reach one of the observation points (3 on the map) in just a short while. Take your time and look around the landing site. You will probably notice that some of the enemy soldiers are using Nanosuits. As a result, you shouldn't attack them (at least - not until you're ready). Instead, try taking out other soldiers. Some of them will be standing near heavy machine gun nests and it would be a good idea to get rid of them.
Now you should move west. Remember to ignore soldiers equipped with Nanosuit armors. Instead, try finding one of the enemy snipers (screen) and make sure he's been killed. There are also other enemy units beneath you. Try and kill most of them from here, so you won't have to deal with them later on during the course of this mission.
You've got two choices here. If you don't want to go back to the upper section of the train tracks, you should try and slide down, so you'll end up somewhere near the train station. Proceed to the carriages right away and approach them from the western side. Use them for cover and start moving south. Obviously you will have to activate camouflage in order to prevent main character from being slaughtered.
You will probably come across a Nanosuit soldier. You will have to be extremely careful here, because he's carrying a powerful minigun. Wait for him to get closer and attack him with a shotgun. Now you should consider exchanging your shotgun for the minigun, especially since you'll have to take out other Nanosuit units in the near future. Wait for other soldiers to show up here before you decide to move forward.
Eventually you should be able to reach a space between two of the largest buildings of the landing area. Look at the screen if you're having some difficulties finding out where exactly to go to. Be careful, though. Some of the enemy soldiers may still be hiding to your left. Kill them, however don't go to the main area of the landing zone, because it's not safe there. Instead, wait for the game to display an updated mission objective.