In 2022 you must book your day and time of arrival in advance. You can choose the day and time when you buy the Tulip Festival Card. So also with a 2 or 3 day card you get 1 day access to Keukenhof. The multi-day card only applies to public transport in Amsterdam and region. However, you can take the Keukenhof bus (858,852,850 or 50) for more than one day and spend an extra day, for example, sightseeing the tulip fields.