There are currently no direct international flights from the UK to Ecuador. Several airlines operate via a variety of European cities, USA cities & Bogota, Colombia.
It is only possible to fly to the Galapagos Islands from Ecuador & they generally operate from Quito via Guayaquil to either Baltra or San Cristobel. As many client trips end with the Galapagos Islands, several of the international airlines offer departing flights from Guayaquil – avoiding the need to return to the higher altitude of Quito
Whilst in Ecuador there are domestic flights, interesting train journeys & road transfers – a great trip to take is from Quito, down the Avenue of Volcanoes, ending in Cuenca to then either fly back to Quito or to Guayaquil.