Latest update to e-visas

The British Foreign Office has confirmed that from the 29^th October you must apply for your e-visa before you travel.

Entry requirements section (Visas) – from 29 October 2018, self service e-Visa kiosks and Wi-Fi areas where visitors can apply for an e-Visa on arrival will no longer be available in Turkish airports; you must apply for your e-Visa before you travel

Source:  https://www.gov.uk/foreign-travel-advice/turkey