Hiking is the preferred term, in Canada and the United States, for a long, vigorous walk, usually on trails (footpaths), in the countryside, while the word walking is used for shorter, particularly urban walks. On the other hand, in the United Kingdom, and the Republic of Ireland, the word “walking” is acceptable to describe all forms of walking, whether it is a walk in the park or backpacking in the Alps.

The word hiking is also often used in the UK, along with rambling (a slightly old-fashioned term), hillwalking, and fell walking (a term mostly used for hillwalking in northern England). The term bushwalking is endemic to Australia, having been adopted by the Sydney Bush Walkers club in 1927. In New Zealand a long, vigorous walk or hike is called tramping. It is a popular activity with numerous hiking organizations worldwide, and studies suggest that all forms of walking have health benefits.

A safari is an overland journey, usually a trip by tourists in Africa. In the past, the trip was often a big-game hunt, but today, safaris are often to observe and photograph wildlife—or hiking and sightseeing, as well.

In 1836 William Cornwallis Harris led an expedition purely to observe and record wildlife and landscapes by the expedition’s members. Harris established the safari style of journey, starting with a not too strenuous rising at first light, an energetic day walking, an afternoon rest then concluding with a formal dinner and telling stories in the evening over drinks and tobacco. The hunting aspect traditionally associated with the safari is said to have its origins in the early 1800s in the region of Évora, Alentejo, where villagers got together to hunt wild boar and reclaim land for farming.

Paragliding is the recreational and competitive adventure sport of flying paragliders: lightweight, free-flying, foot-launched glider aircraft with no rigid primary structure. The pilot sits in a harness suspended below a fabric wing. Wing shape is maintained by the suspension lines, the pressure of air entering vents in the front of the wing, and the aerodynamic forces of the air flowing over the outside.

Despite not using an engine, paraglider flights can last many hours and cover many hundreds of kilometers, though flights of one to two hours and covering some tens of kilometers are more the norm. By skillful exploitation of sources of lift, the pilot may gain height, often climbing to altitudes of a few thousand meters.

Mountaineering is the sport of mountain climbing. While some scholars identify mountaineering-related activities as climbing (rock and ice) and trekking up mountains, others are also adding backpacking, hiking, skiing, via ferrata and wilderness activities, and still others state that mountaineering activities also include indoor climbing, sport climbing and bouldering.However, to most of the scholars, the term mountaineering is understood as climbing (which now refers to adventure climbing or sports climbing) and trekking (hill walking in ‘exotic’ places).Hiking in the mountains can also be a simple form of mountaineering when it involves scrambling, or short stretches of the more basic grades of rock climbing, as well as crossing glaciers.

While mountaineering began as attempts to reach the highest point of unclimbed big mountains, the sport has branched into specializations that address different aspects of the mountain and consists of three areas: rock-craft, snow-craft, and skiing, depending on whether the route chosen is over rock, snow or ice. All require experience, athletic ability, and technical knowledge to maintain safety.

Scuba diving is a mode of underwater diving where the diver uses a self-contained underwater breathing apparatus (scuba) which is completely independent of surface supply, to breathe underwater.Scuba divers carry their own source of breathing gas, usually compressed air, allowing them greater independence and freedom of movement than surface-supplied divers, and longer underwater endurance than breath-hold divers. Open circuit scuba systems discharge the breathing gas into the environment as it is exhaled, and consist of one or more diving cylinders containing breathing gas at high pressure which is supplied to the diver through a regulator.

They may include additional cylinders for range extension, decompression gas or emergency breathing gas. Closed-circuit or semi-closed circuit rebreather scuba systems allow recycling of exhaled gases. The volume of gas used is reduced compared to that of open circuit, so a smaller cylinder or cylinders may be used for an equivalent dive duration. Rebreathers extend the time spent underwater compared to open circuit for the same gas consumption; they produce fewer bubbles and less noise than open circuit scuba which makes them attractive to covert military divers to avoid detection, scientific divers to avoid disturbing marine animals, and media divers to avoid bubble interference.

Tourism is travel for pleasure or business; also the theory and practice of touring, the business of attracting, accommodating, and entertaining tourists, and the business of operating tours. Tourism may be international, or within the traveller’s country. The World Tourism Organization defines tourism more generally, in terms which go “beyond the common perception of tourism as being limited to holiday activity only”, as people “traveling to and staying in places outside their usual environment for not more than one consecutive year for leisure, business and other purposes”.