Amsterdam, a popular tourist place is packed with visitors except in January, February, and March. However, a cautionary note, the weather in these months is cold and rainy.
In September 2023, Athens was thronged by tourists and the authorities were forced to limit numbers to 20,000 per day. This was implemented via an hourly slot system on a booking site. While July, and August are the busiest months, April and May have very few visitors.
July and August are the busiest months. However, the rainy season which generally falls from October to April, means fewer tourists. However, December and January, especially New Year bring substantial crowds.
In Summers, especially July and August Barcelona is bustling with tourists. So, unless you want to struggle with huge crowds avoid these months.
From November through April, the weather in this beachy paradise has amazing weather, which isn't that hot, which means a lot of tourists. So, it is best to avoid these months.
Off-season for this popular destination falls between November and March.