The "Backyard" is my backyard! All 9 acres of it! The boundries are: fence on the back side and hills on the others. It's basically down in a little valley, making it less windy and thus less cold (great for warn December day games) than the surrounding area. The valley aspect also makes is safer. When Joe and I first built the Old Fort and then the Bunker we weren't thinking of "field layout", we just wanted a place to fight over. As time when on and more forts started being needed, it was time to consider the overall layout and how it works or doesn't work with everything else. The "Backyard" is not perfect but were working on it!
Good field layout requires planning. Cover, concealment, lines of sight, & fire lanes, man made or natural, must be considered. "Forts" should be considered as objectives, and, under that philosophy, do not need to be easy to defend, nor should all the forts be too easy to capture. Its good to have some easy, some hard. This helps give variety and balance to the field. Forts as well as bunkers and cover should be positioned in general to provide cover from line of sight "angles" of opposing cover. Of course, a few pieces of cover that are just there don't hurt. Cover that provides angles on opposing cover is useless, even frustrating without a "fire lane". Fire lanes are lines that a projectile from one position may travel unhampered to a receiving target, like Joe, at another position. Cover without fire lanes is just a place to hide behind, or waste paint by breaking it on the brush. However, remove too much brush and concealment is also removed as well as mobility. A fire "lane" implies lack of unobstructed projectile travel outside of the fire lane. Widen these lanes to something like a mowed lawn and your only cover during movement is suppress and/or blowing your paint away in suppressive fire. You then have "speed ball". Not that the ball travel any fasted, they just get used up faster.
The layout of the Backyard takes in to account to greater or lesser degrees all of the above. We do not have a speedball field, but attacking the "Bunker" from the front can be a lot like playing speed ball. We do have some mowed paths. These allow fast (and safer, you can see where you're running) movement and are relatively poison ivy free. Much of the cover & concealment is natural. The not so natural stuff is placed to re-enforce a position, or improve an avenue of attack. This is particularly true of the "Stick Fort". It's difficult to defend from the East, but natural terrain with a few carefully placed supporting bunkers above the "pinch point" makes it very defendable from the North, East, & South. Usable cover outside of a fort is usually set some 20 feet or more away from a fort. The reason is simple, it helps enforce the 20 foot rule. Like wise, opposing bunkers are set at least 20 feet apart. Unfortunately, natural cover and concealment comes up where it will with total disregard to rules. Clearing it out would not only ware me out but turn the place into a 9 acre speed-ball field. So, if you're in concealment, try to shoot the person walking blindly into your ambush before they are too close. The "Bunker Fort" Commands an open section of the pasture. It's second level gives defenders longer range, allowing harassment fire all the way into the "reeds". Dug into a section of the "rise", it is weaker from the rear, but not weak. Lack of man made cover and boundary nearness behind the "Bunker" offsets much of the rear attack disadvantage. The "Bunker" is, and was designed to be the most defendable fort on the field. It is the only fort I will actually seek to move into to defend against 3 or four attackers & expect a fair chance of defending it. Usually, I much prefer mobility over stationary cover. The "Bunker Fort's" protection includes a rim of man made cover, including the "Hog Pen" so named because it resembled a "Little Abner" like hog pen, but unlike the comic strip name sake, this commands a defensive position on the corner of the "rise". If taken by the attackers, it also provides cover & concealment for sharpshooters to eliminate Bunker's defenders. This is true all of the Bunker's rim cover with exception of the two directly, and well within 20 feet behind the Bunker. Their position and angle will work well for the defenders, but give little cover for the attackers.
Within range of the Bunker is the "Corner Fort" so named because it sits it the corner of the field boundaries. This corner position gives the simple Corner Fort it's best defensive properties. Also, there is little in the way of good close range cover and concealment, giving the Corner Fort some 50 feet of relatively open field of fire.
About 100 feet further South and on the edge of the "rise" stands the "Log Fort". Got its named because of my habit of turning fallen trees into forts or bunkers. There are a lot of trees near the Log Fort. It sits on the edge of the rise, overlooking the West edge of the pasture. The fort has a definite advantage from pasture a assault. Only one bunker stands in opposition directly 80 plus feet in front of it. In the summer, there is also a lot of undergrowth concealment. This concealment actually makes the fort vunerable from aggressive attack from Corner Fort or the creek. Fire lanes are narrow. Attackers coordinating their efforts can "leap frog" the cover between Corner and Log forts. The same is true to a lessor extent from the creek and reeds. Although man made cover is scarce on the creek side, concealment is good. Unless the Log Fort defenders are attentive, stealthy attackers can find lines of fire that compromise the Fort's defenses.
Just across the creek with it's back close to the West boundary line is the "Old Fort". The Southern boundary is also in easy reach of "Old Fort" guns, but the bold & lucky or the stealthy attacker may be able to reach concealment from which they may reach lines of sight on the fort's vunerable hindside. It faces an open pasture with a row of bunkers about 40 - 50 feet in front. It's North side is bordered by the creek and has good fire lanes into and small lanes across it. The creek side is opposed by a few stick bunkers and good concealment just across the creek. It has been rebuild over the Winter of '01 from a fall-back-to-as-a-last-resort fort to a bi-level, cancelled ad back a few feet to keep the creek from claiming it when high waters changed the bank from easy to goat tough. This fort is constructed mostly of discarded pallet layer dividers. Those 42" x 39" sheets of plywood can be drilled at the four corners & wired together for instant bunker or fort. The crossing fort stands just below the "pinch point" and provides a sheltered observation point of a good stretch of creek bed and the reeds beyond. To the West is open grass with a large stand of hedge tree between it and the Old Fort. The South side is closely bordered by light timber with turns into concealment in the Summer. Because of a good range of fire and movement hampered by terrain, despite it's simplicity, the Crossing Fort is not easy to attack.
On the same side of the creek, East and just out of range of the Old Fort is the "Crossing Fort" This fort got is name from the easy place to cross the creek that it closely guarded. The fort had to be movend a little East from the Crossing Fort is the "Dead Man's Fort". Made of wired pallet dividers that once were bunkers for a short lived speed ball field, the Dead Man's Fort got it's name from it's role in scenario game. Rather centrally located, this "fort" was a rally point where those eliminated could signoff and rejoin the living at a friendly fort, if any remained friendly.

Directly 200 plus feet East is the "Bridge Fort" that is build on the pillars of the Bridge.
The two level fort looks down & over the creek and mowed lawn on three sides. Wide open fire lanes, little near concealment, and light cover make the Bridge Fort tough from three sides, but it is relatively open to the rear and vunerable for the attacker lucky enough to reach a rear line of sight.