There are zero airlines offering flights to Berlin. The most direct route isn’t necessarily the cheapest – being flexible is key to finding the lowest airfare rates. For example, try searching by month to see the best time of the week to fly.
Make sure you use the search options above to search for flights to other airports in Berlin, not just Berlin-tegel / Otto Lilienthal Airport. The more options you look at, the better your chance of finding a cheap deal.
During this peak season, hotel and holiday prices often increase too, so it's best to book early. Or you could keep your fingers crossed and hold out for a last-minute deal.