A wide variety of destinations, reasons for and modes of travel may be involved including climbing mountains, crossing deserts, river cruises, exploring jungles, visiting game parks, crossing oceans and traversing polar ice caps.
They can, for example, involve trekking (walking), horse riding, cycling, sailing, motorised transport or even flying.
Safari holidays to study wildlife such as animals and birds can include expeditions usually with a guide.
They often involve groups travelling together with leaders to areas where the average tourist would not consider going.
The ease of modern-day travel has made expeditions to distant places popular. They are often, but not always, well organised, well equipped and with experienced guides.
There are organisations which arrange expeditions for teenagers such as Scouting, Raleigh International and World Challenge where there is an emphasis put on developing personal life skills and cooperating as a team in challenging circumstances.
Those travelling on expeditions go to many different types of environment.
For example, they may find themselves in very hot or cold climates, the jungle, outback areas and deserts or at high altitude.
Expeditions frequently include overland trekking interspersed with transport by overland vehicles and sometimes on water. Each of these modes of transport and activities carries specific challenges and levels of risk.
Good organisations will take care to ensure their participants are both physically and mentally suitable for their particular expeditions.
However personal research into what is involved is essential, perhaps by speaking to previous participants. Paying particular attention to possible health risks related to their destination and planned activities is also very important.
It is unusual for expedition organisations to now universally exclude elderly participants. The fitness of the participant is usually considered more important but the organisers may ask for a medical report from the participant's doctor.
Expedition leaders should advise in detail on the intended route(s), modes of transport, accommodation and what personal clothing and other equipment is necessary.
Considering social skills is essential. When people have never met before and then have to travel, live and work together, often in a stressful environment and when collective decisions are required, personality clashes or even ‘power struggles’ are frequent.
Other preparations as described elsewhere in the courses, for example, on climate differences, cultural change and exposure to infections are equally important for expeditions.
The importance of well trained and qualified guides cannot be overemphasised. This is essential for the inexperienced traveller but also for those with experience going to places or will be in circumstances with which they are unfamiliar.
Well-organised sporting and expedition leaders give a lot of consideration to preventing accidents and providing first aid if they occur.
These can range from falls, accidents in water including drowning, to being attacked unexpectedly by animals such as dogs, lions and tigers and crocodiles. Many animals, including rhinoceroses and hippopotami protecting their young, can be extremely dangerous.
These risks need to be considered during the planning stage on expeditions and take into account the availability of any medical care during the journey.
The need for comprehensive insurance, including cover for accidents, cannot be emphasised too strongly. Most insurance companies will ask about specific high-risk activities before they quote a price
The need for comprehensive travel insurance must be emphasised and is usually obligatory. Applications for travel insurance must include all intended and likely activities.
This is likely to be more expensive than for package holidays.
Remeber that if the organisers provide group insurance, this is not likely to cover a person's existing illnesses.
Travelling quickly in emergencies from remote areas can be difficult and may take many days, for example in bad weather.
The Exploration and Expedition Medicine website is an excellent resource and includes information about leadership skills and courses for those going to more remote places.