Visas are not needed for nationals of the UK, Germany, Italy, Australia, Belgium, Canada, Luxembourg, the Netherlands, New Zealand, and Scandinavian and Ecowas countries for stays of up to 90 days.
A yellow-fever vaccination certificate is required of travellers coming from an infected area.
For those needing one, visas are normally valid for one or three months and cost D1000 or 4000; these are available upon arrival. The Immigration Office in Banjul deals with visa extensions.
If you are travelling overland, you can buy a visa at the border with Senegal; typical cost is around D3000 for a single-entry visa valid for one week. The visa should be available at all border crossings.
For onward travel, get your visa from the relevant embassy. Most embassies will deal with requests within 48 hours.
There are no particular restrictions on taking Gambian items out of the country – apart from the obvious prohibitions of illegal drugs, meat, plants, and any part of an endangered animal (skin, turtle shell, horns).