Morocco - None needed for many nationalities
Mauritania - Rabat, Morocco - 93€ - Same day or on the border for 120€
Senegal - Casablanca, Morocco - instant - free
The Gambia - At the border (But they will try to sell you one

)
Mali - Got at home, 100€ - Get in Dakar Senegal
Ivory Coast - Dakar - 45€ - 2 days
Ghana — Rabat, Morocco - 50€ (+20€ oil for the cogs) - 1 day - (Get at home if possible)
Togo - At southern border (7 days) or in Accra Ghana - 16€
Benin - Accra, Ghana - 76€ for 15 days
Nigeria - Get at home or in Bamako, Mali - 50€ (GET THIS ONE!)
Cameroon - Calabar, Nigeria - 68€ - Same day
Gabon - Lomé Togo - 75€ - Next day
Congo Brazzaville - Lomé Togo - 90€ - Instant
Congo Kinshasa - Cotonou, Benin - 22€ - 8 day transit - Instant
Angola - Accra, Ghana - 160USD - Two days
Namibia - Free on border
South Africa - Free on border
For sure check your own requirements, but if you need a visa you can get it at these places. I’m on a New Zealand Passport (Same same as EU/US/AUS).
A total cost of 865€ just on visas plus 150€ for two visas that expired or I got new ones to be safe. Plus the cost of running around and hotels to get the visas.
But it's worth it! COME TO WEST AFRICA!
Currently in Benin -->
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