Yes, you are more than welcome to do so! We can assure you that your trip will be even more fun with the added activities. You can pay for the extra activities directly online with a credit card.
Please note that extra activities can only be booked online up to 7 days before the departure.
In order to add more activities to your trip booking, please log into your Customer Account and navigate to your Dashboard. You should see your reserved trip along with an option to book Extras. If this option is not visible to you it is most likely due that your reservation is not paid yet and thus you cannot yet add to it.