https://www.trip.com/blog/the-10-hardest-countries-to-visit-from-a-guy-whos-visited-them-all/

https://www.insider.com/world-travel-sites-attractions-hard-to-visit

https://www.veryhungrynomads.com/hardest-countries-visit/

https://www.thetravel.com/most-difficult-places-american-citizen-visa/

https://www.rd.com/list/the-worlds-most-dangerous-tourist-destinations/

https://www.traveller.com.au/worlds-most-remote-places-the-hardest-territories-on-earth-to-get-to-gmbxfm

https://www.cnn.com/travel/article/most-remote-islands/index.html

https://www.cnn.com/travel/article/americans-hardest-countries-to-visit/index.html