Arkansas is a land of mountains and valleys, thick forests and fertile plains. The so-called Lowlands are better known by names of their two regions, the Delta and the Grand Prairie. The Arkansas Delta is a flat landscape of rich alluvial soils formed by repeated flooding of the adjacent Mississippi. Further away from the river, in the southeast portion of the state, the Grand Prairie consists of a more undulating landscape. Both are fertile agricultural areas.

The Delta region is bisected by an unusual geological formation known as Crowley's Ridge. A narrow band of rolling hills, Crowley's Ridge rises from 250 to 500 feet (150 m) above the surrounding alluvial plain and underlies many of the major towns of eastern Arkansas.

Northwest Arkansas is part of the Ozark Plateau including the Boston Mountains, to the south are the Ouachita Mountains and these regions are divided by the Arkansas River; the southern and eastern parts of Arkansas are called the Lowlands. All of these mountains ranges are part of the U.S. Interior Highlands region, the only major mountainous region between the Rocky Mountains and the Appalachian Mountains. The highest point in the state is Mount Magazine in the Ozark Mountains; it rises to 2,753 feet (839 m) above sea level.

Arkansas is home to many caves, such as Blanchard Springs Caverns. It is currently the only U.S. state in which diamonds are mined.

Inflatable structures are large cold air inflatables that people (usually children) can enter and bounce around on. They have been marketed under a variety of names: Astrojump, moonwalk, bounce house, moon bounce, or jolly jump in the US, bouncy castle or inflatable castle in the UK and parts of Australia, and as jumping castles in Australia, New Zealand, Canada and South Africa. They are often in the shape of a castle but can be made into a variety of designs. The walls and floor are both bouncy, like a trampoline.

The original inflatable structure was designed in 1959 by John Scurlock. He was experimenting with inflatable covers for tennis courts when he noticed his employees enjoyed jumping on the covers. He started the Space Walk company to market them for children and called them Space Walks. He started out with a large air mattress. In 1967-1968, he decided to add walls. The windows were made of solid clear plastic and were enclosed like a bubble- one fan inflated the base while another inflated the bubble and circulated air for the riders.

Inflatable structures were also designed by university students in England around 1961 for a fundraising event.

The surfaces are typically composed of thick, strong PVC or vinyl and nylon, and the castle is inflated using an electric or petrol-powered blower. The principle is one of constant leakage, meaning small punctures are not a problem, although this means the fans need to be quite powerful; a medium-size "bouncy castle" requires a fan with a mechanical output of about two horsepower (consuming around 2 kW electrical power, allowing for the efficiency of the motor).

The term "moonwalk" has evolved as the generic term for enclosed inflatable trampolines in the US. Modern moonwalks in the US are typically supported by inflatable columns and enclosed with netting to allow air to pass through.The netting also allows for proper supervision as adults can see in from all sides.

UK and Australian bouncy castles have different specifications calling for fully inflated walls on 3 sides with an open front and foam "crash mats" to catch children who may jump or fall out of the structure.

Inflatables are most commonly rented for private functions, school and church festivals and village fetes. Although they are aimed at children, adult castles can be hired in the UK. Because of liability concerns moonwalks are rarely rented to adults in the US. They are often used to wrestle, bounce or rumble. Recently, a theatrical group has started performing Shakespearian tragedies on bouncy castles at the Edinburgh Fringe Festival (Hamlet in 2006, Macbeth in 2007).

The growth in popularity of standard moonwalks has led to an entire inflatable amusement industry which includes inflatable slides, obstacle courses, games, and more. Inflatables are ideal for portable amusements because they are relatively easy to transport and store but make a big impact when fully inflated.