Board your economy class flight from Kathmandu to Istanbul with a reputable carrier, likely Turkish Airlines, which offers cost-effective options and convenient stopovers.
Check in at a 3-4 star hotel such as Radisson Blu Hotel, Istanbul Sisli, which offers comfortable rooms and complimentary breakfast, facilitating rest for your stopover.
Explore iconic Istanbul landmarks such as Hagia Sophia and the Blue Mosque, open from 9AM to 7PM, to experience some local culture during your layover.
Entry Free for Blue Mosque, Hagia Sophia approx. USD15, 3h0m
Check in to a central 3-4 star hotel such as Hotel Panamby São Paulo or Transamerica Executive Jardins featuring free breakfast and comfortable accommodations.