We first started putting swim steps on our designs in 1978. Initially they were a safety device, a way to make man overboard recovery easier.
We quickly learned that these steps were also great for getting into and out of the dinghy, and for swimming. With a little extra space turned into a locker(s), the swim step was the perfect place to store flammable materials.
On a single engine design, with centerline prop and rudder, we are always fighting for enough space and storage volume. But once twin engines and rudders are in the equation, a recessed stairway can be placed between the rudder shafts and related steering gear, and the step itself can be deeper. This allows for an easy-to-use tread layout (we normally have a steeper ladder here).
There is a tradeoff between storage space, in this case on either side of that good-looking model, and room getting into and out of the dinghy. Here there is room for one of us to stand or squat on the swim step while holding the dink, while a second person gets into or out of it.
The swim ladder is hinged on the aft edge of the step, on the port side. When not in use, the ladder resides in the stored position shown above. When we are cruising there is a short piece of line, with a knot on the end, which runs from the first ladder rung to just above the waterline. This makes it easy to pull the ladder to you, should you take an inadvertent swim.
We have a huge amount of storage in lockers welded onto the hull. On the port side we keep our propane. There are three 20-pound (9kg) bottles in here, plus additional room for snorkeling gear. The propane inventory is enough for seven to eight months of cruising.
Opposite is our dinghy gasoline storage. There is space for four tanks, each of 6-gallon (23-liter) capacity, in addition to the tank in the dinghy itself.
Here is the view from the aft deck looking down. This was taken at Fanning Island, a stop on our way to Hawaii from Samoa. The two men in the inflatable are Kiribati Customs and Immigration officers.