The Layout
Our club located in a 90' X 45' basement. It's built in the peninsula style - there is one main backbone down the 90' wall, and we have 5 peninsulas extending out in a 'finger like' fashion.
This diagram shows how our layout is set up in a peninsula fashion. A backbone (top) goes alone the far wall, with the layout weaving out and back along each peninsula. (The 5th peninsula (right most) as built is different than this diagram shows)

Each peninsula has a partition that goes from layout to ceiling, so you cannot see between the peninsulas. This give the nice effect of making the layout seem bigger than it is. It also makes it seem more like the trains are "going somewhere" as you run them around the layout.
Most of the layout is HO scale (1:87). The 3rd peninsula has HOn3 town and mine branch. The 5th peninsula has plans for a trolly segment (HO Scale)
Construction
Given out layout has been under construction for over 25 years, we have many different construction methods in place.
Most of the bench mark is made of 2X4 L-girder bench work. Most yards are on hard surfaces; some plywood, some homasote (in our younger days). The mainline consists of a mix of hand-built spline (older) to cut plywood (today). All of our current work, we outline the trackage on plywood, and cut the mainline out. The main line is supported by supports from the bench work to the appropriate elevations.
Track
All of the visible track is hand-laid track - that is someone actually lays down ties, and then spikes rails to the ties. A lot of work, but that's their hobby
All track surfaces are prepared by first laying down a roadbed of Aspen. Ties are then glued down, and the surface sanded smooth. Rail (usually code 83) is then laid down and spiked in place. All of our switches are also hand built in place. This gives us greater control over off curvatures and such in out layout - it lets us be more creative in our track plans.
Control
Our layout has a basic walk-around DC throttle system. We are introducing DCC to the layout - you can find more about our DCC setup from the menus above. A bit about how our DC system is set up continues below.
The layout is separated into many different isolated blocks. If you want to run a train around the layout, you have to insert a shorting pin into a throttle jack for each block of your route. So, if you are using cab 3, you must pin the block jacks into number 3 as you proceed around the layout. Other operators can pin their blocks for different cab numbers. This block system allows up to 9 DC operators to operate the layout simultaneously.
We used to have 10 control cabs, but cab 1 is now being used for DCC control.
Speed is control by a basic hand-held throttle with two buttons. These buttons control your acceleration either forward or backwards (or, east and west). They do this by shorting one of two connections in the hand held, thus applying either a + or (-) voltage to the tracks.
Pressing and releasing a button applies voltage (speed) in that direction. The throttles have memory, and the trains will maintain their current speed without having to hold a button in, or while moving the throttle from one jack to another. The whole throttle control system is based on a control system designed by Don Fiehmann published in RMC about 1977