It can get moderately to very crowded, especially on weekends.
The Maritime Vlaardingen Market can attract a significant number of visitors, especially during peak hours on Saturday afternoons and Sundays. It can become moderately to very crowded, particularly along the main market aisles and around popular ships. If you prefer a less crowded experience, consider arriving early in the morning on the first day of the event. The atmosphere, however, remains festive even with crowds.