Borneo can be visited year-round - but this is the driest season, so the best time for visiting the rainforest and Mt Kinabalu.
South Africa and Namibia are very dry so wildlife will congregate around waterholes, making this a great time for safaris in Kruger and Etosha, but book well in advance. Botswana is also fantastic for wildlife viewing as the Okavango Delta is at its fullest. Temperatures are warming across the region as well, so you'll miss the worst of the nighttime chill.
September is the best time to visit Brazil - you'll avoid the rainy season, the worst of the crowds and the crazy summer heat in the north.
This is one of the best months to see the Northern Lights in Iceland, as they're said to be more likely around the equinox. There's still some daylight, meaning you can get out and do other activities.
Norway can have some lovely mild weather at this time, along with very long daylight hours - and few other visitors.
Although Thailand's Andaman Coast gets the worst of the monsoons, the climate in the Gulf of Thailand is drier at this time - so if you really want to visit Thailand in the autumn, head to the east coast.
You can still see the Great Migration in Kenya and Tanzania - including the Mara River crossing. But the summer crowds have dispersed - so you'll have a much better view!
Where NOT to go on holiday in September
This is the monsoon season across mainland Southeast Asia and southern India, causing travel disruption in most of the region, with some hotels and roads closing.
It's hurricane season in Cuba - with the southeast being the worst affected.