As Michal has explained - BOTH are correct. The version with one 'l' is used in American English, the version with two 'll's is used in British English. This rule applies to all derivates of the verb: travelling, travelled, traveller - BrE traveling, traveled, traveler AmE It also applies to other verbs ending in an unstressed 'el', for example: fuelling, channelling - BrE fueling, channeling - AmE

Both versions are correct. Traveling is American English , travelling is British English

"traveling" is correct.

"traveling" is correct.

travelling