Victorville, Calif. -- The Marines of 3rd Battalion, 7th Marines returned Monday from Victorville, where they were helping the Marine Corps Warfighting Lab test the efficiency of its Basic Urban Skills Training package. The three-week package, which took place June 12-30, is a part of Project Metropolis, an initiative to teach Marines how to carry out peacekeeping, civil disturbance, and high-intensity combat operations in built-up, highly-populated areas. General Charles Krulak developed this three-block concept of urban fighting during his term as Commandant of the Marine Corps."In one moment in time, our service members will be feeding and clothing displaced refugees, providing humanitarian assistance. In the next moment, they will be holding two warring tribes apart, conducting peacekeeping operations. Finally, they will be fighting a highly-lethal, mid-intensity battle," said Gen. Krulak. "All on the same day, all within three city blocks. It will be what we call the three-block war." According to Maj. Dan Sullivan, officer in charge of Project Metropolis, Marine Corps Warfighting Lab, the package is in the latter stages of development. "We've been developing the training for two and a half years," said Sullivan. "It used to consist exclusively of the high-intensity operations, but we're working now to add security operations and peacekeeping into one comprehensive package." The first week of training consisted of a combination of classroom lectures and practical application to learn the basic skills of urban warfare including movement, breeching and cleaving. "It's really a crawl, walk, run approach," said Sullivan. "We begin at day one learning individual skills all the way up to battalion-level combat movements at the end." The second week, the Marines of 3/7 focused on squad, platoon, and company attacks, followed by extensive debriefs to analyze what took place and discuss any complications in the training process. During this portion, the instructors paid extra attention to small-unit leadership, a vital component of winning battles on urban terrain. "Urban warfare is really decentralized, unlike mechanized operations where the battalion commander runs the battle," said Lt. Col. Michael Belcher, commanding officer, 3/7. "The small-unit leader has to pull the fight because the troops are so spread out. It really empowers the NCO and lets them make important decisions." Belcher added that communication is key in order to make proper decisions to protect the troops and accomplish the mission. "It's so easy to get isolated and lost in the urban canyons, making communication extremely important," said Belcher. "It's necessary to have a way to send signals, whether by small radios, smoke or visual systems, to let other Marines know your location. That's hard to do when you're in a building or underground in the sewer systems." During the final week of training, the Marines spent five days learning and practicing peacemaking operations, also known as Block Two. The culminating event was a 48-hour battalion field exercise where 3/7 had an opportunity to practice the skills they adopted during their intensive training. The final exercise, as well as much of the previous training, took place in an area known as "The Box," an abandoned neighborhood aboard the Southern California Logistics Airport that used to be George Air Force Base in Victorville. According to Lance Cpl. Michael Lally, armorer, 3/7, the old base made for a perfect training environment. "The Box provided us with all the characteristics of an urban war zone for us to train," said Lally. "It's definitely a different kind of playing field. Because of the three-dimensional environment, there could be enemy to your left, right, or even above you." During the final exercise, Marines were pulled from the battalion to play the opposing force, civilian inhabitants, and even reporters. "The point is to try and make it as accurate as possible," said Sullivan. "In an urban environment, Marines have to deal with innocent lives, possible terrorist threats, and an enemy that will possibly be dressed in civilian clothes. Situational awareness is extremely important in order to discern who is the enemy and who is not." The battalion field exercise was also a dress rehearsal for the Urban Combined Arms Exercise scheduled for August 9-12. The purpose of U-CAX is to test the efficiency of the MOUT training package. "The Warfighting Lab is validating this package to present it to Headquarters Marine Corps," said Belcher. "They've given us the training package, and they'll test us to see how well we do when it comes to the actual force-on-force operation." During U-CAX, the Marines of 1st Battalion, 1st Marines, who just returned from fighting a real urban war in Afghanistan, will act as the opposing force. The military will hire 100 civilians to play the neighborhood inhabitants. "The U-CAX will be a much more elaborate stage production than the field exercise and will provide a more accurate depiction of the reality of urban warfare," said Sullivan. After the exercise is over, analysts and subject-matter experts will analyze the collected data such as casualties taken, nature of the casualties, and time taken to accomplish each mission, to determine if the Marines were properly trained during the three-week package. "At that point, we'll have taken it as far as we can take it," said Sullivan. The Marine Corps Warfighting Lab will host an assessment conference with key officials in Quantico, Va. in October. "I really hope this training gets on the ground for all Marines soon because it is of the utmost importance," said Sgt. Thomas Cox, scout/sniper platoon sergeant, 3/7. "It's quite evident that future conflicts will be taking place in urban environments."