So, after failing miserably with the first two entrance designs in Dwarf Fortress, I went back to the drawing board. When starting out a new embark (a.k.a new game or expedition), you need to accomplish a few things right off the bat:

• Assign dwarfs to tasks: 2/7 (two of seven) dwarfs should be mining, 2/7 should be capable of wood cutting, 2/7 should be capable of gathering plants. Ignore things like bookkeeping, broker, militia. Assign a dwarf to be the chief medical dwarf.
  
• Make sure you have (1) carpenter, (1) mason and (1) mechanic assigned to your dwarfs as secondary skills. Generally, the wood cutters get assigned "carpenter" and "mechanic" skills. One of the plant gatherers gets assigned as a mason. (But as you get more skilled, look at their strengths/talents before you assign willy-nilly.) You should also tack on the "Architect" skill to one of the dwarfs.
  
• You will need to have at least 2-3 levels of dirt/rock above your initial fortress. Ideally, this means digging into the side of a hill, but could also mean just digging down out in a flat plain. If you're working with rivers/ocean, you're really going to want to be able to dig upwards from ground level at first (which means parking up against a hillside).
  
• Since you will need fresh water, placing your entrance area near rivers or muddy pools of water (multiple pools) works well. You can setup an underground canal to draw from a river/ocean or simply drain a muddy pool into an underground room (a.k.a making a cistern).
  
• In 31.18 of Dwarf Fortress, you will have to create underground fields for farming. This requires digging out a room, then flooding it with water, then letting it dry out. Muddy pools work well for this as they are "finite" sources of water, so things can't get horribly out of control. You probably won't be able to plant these until mid-Summer.
  
• You will need to come up with a basic plan for an entrance tunnel, a less secure outer area, and a more secure inner area. During the first season, go for simple with a 1-2 tile wide corridor for the entrance. The initial burrow will typically only be 40-60 tiles wide and 20-30 tiles tall, with an entrance of 15-30 tiles in length.
  
• Wait until the end of your first Spring to build a Trade Depot.
  
• To make a floodgate, you need (1) floodgate (usually made from non-economic stone using Masonry skill and a Mason's workshop) and (3) mechanisms (generally also made with stone but at a Mechanic workshop). One mechanism is for the lever, the other two are to link the floodgate to the lever.
  
• You should designate a refuse pile and corpse pile right off the bat, along with a small 3x5 furniture pile and a 5x5 wood pile.
  
• Build a carpenter's workshop, a mason's workshop and a mechanic's workshop outside near the wagon and the material stockpiles.
  

First off, let's use Overseer 3D to get a general view of the lay of the land. As you can see, this is a rather flat map, but with 1Z-10Z hills along the east edge. There's a nice river that runs across the west side of the map. Our initial embark point was around where the Trade Depot is. Note that since this is a "temperate" embark location, the river will freeze up during the winter (yet another source of "fun").



There were (2) muddy pools right near our embark location. I drained one into an underground 3x3 cistern that is about 3Z tall, while the smaller one got drained to create a set of five 3x5 tile underground planting fields. It takes almost a full season for that to dry out enough to be planted, so it's probably one of the first things you should dig out.

Our entrance tunnel is rather modest (1-3 tiles wide), but you can see that I started rather large (11x11) future main entrance cut. I placed this large cut about 15-30 tiles away from the entrance location and will use it when I build the proper fortress in a few years. It also served as a quick source of non-economic stone. It will eventually involve massive fortifications, moats, bridges, and all sorts of other fun buildings.

That big quarry was created by marking out my corners mentally, then starting at the very top level and digging a channel ([d][h]). Remove any upward slopes inside the channeled area (go down a Z-level) using [d][z]. Then repeat cutting a new channel area with [d][h]. Removal of the upward slopes gives you sides that are not climbable.

Here are some close-up shots of the entrance area. These will give you an idea of what the initial entrance looks like. It's nothing more then a single-tile corridor cut into the face of a hill. Note that you don't need to use Overseer3D to get a view of the surface, but it may help you to make some early design decisions.









Now for a quick view of the (4) main levels of what I've done so far. These are listed in order of lowest (Z-level 143) to highest (Z146). The (3) main levels are generally mirrored upward/downward as much as possible. This makes it easier to remember where I am and it gets easier to memorize the layout. Unlike some more fractal designs, here there are only (2) stairwells in the main area. They are placed in the entrance lobby after the second long hallway running north/south (see Z144). Ideally, I should have placed (4) stairwells here, but two is enough at the start.

Z143 is the "basement" of my initial fortress. It will be used mostly for storage and the heavier workshops. The red stone is "kaolinite" and is a non-economic stone used for Masonry or other stone crafting tasks. The white stone is "limestone" and the dark grey is "slate". Notice that I have one room setup as a "finished goods" stockpile, another as "mechanisms, doors, beds", another as barrels, one for "bins, boxes and bags", along with a mechanic's workshop (near the mechanisms stockpile).

Main corridors in the initial fortress are two tiles wide, but side corridors only need to be one tile wide. Dwarfs can pass each other in a one tile corridor, but it eats up a small amount of time when they collide. So wider corridors are needed in the bigger fortresses.



Note that all workshop rooms are 4x3 with a door. This allows me to wall off (by "forbidding" the door with [q][l][o]) any dwarfs that get into a "strange mood", take over a workshop, but then can't get the raw materials that they need in order to complete their masterwork. After a while, they go insane, and this lets me trap them inside the room so they can't hurt other dwarfs.

Z144 is the "main" level. The purple skull area is the refuse pile, the trade depot is a bit west of that outside. The 3x3 yellow area in the lower-left is the initial embark wagon location. We guard the entrance with a tied up stray dog ([b][v] to place the chain then [q][a] to assign an animal) as a sentry to the doorway. Dwarfs can walk past the chained animal, even in a one-tile corridor and it acts as an early warning.

Next we have a corridor with (4) drawbridges ([b][g][w/a/x/d or s] then [kkk][uuu] to size). These can be closed to form walls along the east edge (we picked [d] to indicate they close to the east) which blocks ingress of enemies. Initially, I only built the first and last bridge. In the narrower sections of the corridor I have placed cage traps. For the first year or so, this will be the primary line of defense.

North of that is the brown farm fields, with a tunnel on the west side protected by a floodgate and leading upwards to a muddy pool that we drained. When laying out a farm area, the approximate math is to take the number of squares in the pool, multiple by seven, and this is the maximum number of tiles that you can irrigate after opening the floodgate to drain the pool. In reality, the workable number is more like 5x to 6x of the size of the pool. That assumes that the pool was filled with 7-deep water to start with (water has 7 depths, if one tile has deeper water then a neighbor, then it will drain into the neighboring tile).

I build my farms with (2) floodgates, one at each end of the room. Close the exit, open the water source side and the room floods nicely without overflowing. Close the intake, open the exit gate and any excess water will flood into the hallway until it is all 0/7 (mud) or 1/7 depth (puddle). Puddles will evaporate after a few weeks, leaving behind mud for farming. If you don't want to fiddle with the second floodgate on the exit, then put the farm down one more level with the exit being an upward ramp.

You'll notice that I put (2) rooms right by the farms, with stairs leading up/down (the grey "X" symbols). This is for seed storage, empty barrel storage and anything else that should be kept close to the farm. Note that because this is connected to the farm (which connects to outside via the water intake tunnel) it should be considered an "insecure" area. So keep this area small and plan on losing it early in a siege/ambush. But only really nasty enemies can break down a closed floodgate and if one shows up this early, it's probably game-over anyway.

The next major feature here is a 2-tile corridor leading north into the fortress proper. Again, this is protected by a 2x2 drawbridge that opens to the North. It should be backed up by a 2nd drawbridge down the road. Lots of future storage rooms are planned out.



Z145 is the "upper" level of the starter fort. The "well" is on the upper level here and connects to an underground cistern via a deep shaft leading down. This level is primary food/ale storage along with rooms for sleeping, meeting, barracks, etc.



Z146 is shown so that you can see that there's nothing above the upper level and it also shows the big 11x11 cut to the south where the future main fortress will be located.



If all that seems a bit confusing, here is an annotated view of Z144.



This is not an ideal setup by any means, but the first fortress generally isn't. The goal of the first fortress at an embark location is to get your dwarfs underground quickly with a small amount of security.