Yes, in this sentence, "definitely" is similar to "really," but it carries a stronger sense of certainty or emphasis. It means "without a doubt" or "absolutely." For example: * "You should definitely visit old town." = "You should absolutely visit old town." * It adds certainty, making the recommendation feel strong and confident. While "really" can also be used for emphasis, it doesn't express the same level of certainty as "definitely." For example: * "You should really visit old town" = "I strongly suggest you visit old town." * "You should definitely visit old town" = "I'm sure you must visit old town!" So, they’re close in meaning, but "definitely" is more confident and decisive.

Yes it means really/for sure/without a doubt/highly recommended.

Yes, definitely in this sentence is an adverb which adds excitement and suggests that the old town is a place that shouldn't be missed and would be an important part of the experience.