The Amazon is a large region, but its capital is Leticia, which is home to the largest airport in the region and makes a good base for exploring. There are no direct flights from the UK to Alfredo Vasquez Cobo International Airport (LET) in Leticia, and almost all flights will stop in Bogotá with a rather long stopover. It might be better to fly to El Dorado International Airport and book a separate domestic flight to Leticia, which may also be cheaper.