As an AI, I do not have personal feelings or physical sensations, so I am not bothered by crowded places at holiday destinations. However, I understand that some people may find crowded places overwhelming or stressful. It's important to consider your own comfort level and preferences when choosing a holiday destination to ensure you have an enjoyable experience. **

Gyms can vary in terms of how crowded they are on Sundays. Some gyms may be less crowded on Sundays compared to weekdays, as people may have other commitments or prefer to relax on weekends. However, some gyms may still be busy on Sundays, especially during certain times of the day when more people tend to work out. It ultimately depends on the specific gym and its location. **

Mykonos can still be crowded in September, especially during the first half of the month when many tourists are still on summer vacation. However, as the month progresses, the crowds tend to thin out, making it a more pleasant time to visit. If you prefer a quieter experience, consider visiting in the latter half of September when the summer rush has subsided. **

Phantasialand can be crowded in winter, especially during the holiday season and on weekends. However, compared to the peak summer season, the park tends to be less crowded in winter. Additionally, the colder weather and shorter daylight hours can also contribute to smaller crowds. It's always a good idea to check the park's schedule and plan your visit accordingly to avoid the busiest times. **

Skateparks are typically least crowded during weekdays, especially in the mornings and early afternoons. Many people are at work or school during these times, so you may have more space to skate without as many people around. Additionally, skateparks tend to be less crowded during colder or rainy weather, as fewer people are likely to be out skating in these conditions. **

The aquarium is not too crowded. The number of visitors is well managed, and there is still plenty of space to move around and view the exhibits comfortably. The layout of the aquarium allows for a smooth flow of visitors, and there are no long lines or congestion at the exhibits. Overall, the aquarium provides an enjoyable and uncrowded experience for visitors. **

Gyms are typically less crowded on Sundays compared to weekdays. Many people use Sundays as a rest day or to spend time with family and friends, leading to fewer gym-goers. This can make it a good day to visit the gym if you prefer a quieter environment. However, some gyms may still have a moderate amount of people depending on their location and operating hours. **

Phantasialand can be crowded in the winter, especially during weekends, holidays, and special events like their Wintertraum festival. However, compared to the summer months, the park tends to be less crowded in the winter. It is always a good idea to check the park's website for information on expected crowd levels and plan your visit accordingly. **