If you want to call home whilst travelling abroad anothertravel.com has put together a complete list of international IDD country and city codes and International Dialling Codes numbers for your reference.
DIALLING PROCEDURE - The (IDD) number is the code you must call to get a line outside the country you are currently in. Therefore this is the first number you need to dial. Next dial the country code for the country you are calling to followed by the area/city code and number. When you see this symbol ~ you must wait for a second tone before continuing. (i.e. if you have 6~8 dial 6 then wait for the tone then dial 8 and the rest of the number) When you see this symbol * dial 1 + area code + phone number if calling from the USA or Canada, from all other countries dial IDD + 1 + area code + phone number.
To find the required country dialling code simply scroll down and select from the list below your desired country. City codes will be displayed on the relevant pages.