Here is a route:
Starting Point: James Scott Memorial Fountain at Belle Isle, Detroit, Michigan, USA
Leg 1: USA to Santos, Sao Paulo, Brazil (DTW>IAH/MIA>GRU, Bus to Santos)
Leg 2: Santos to Porto Alegre, Rio Grande do Sul, Brazil (bus via Sao Paulo)
Leg 3: Brazil to Punta del Este, Uruguay (via bus)
Leg 4: Uruguay to Bloemfontein, Free State, South Africa (MVD>GRU>JNB>BFN)
Leg 5: South Africa to Maseru, Lesotho (via bus)
Leg 6: Lesotho to Linz, Austria (MSU>JNB>FRA>LNZ)
Leg 7: Linz to Innsbruck, Tyrol, Austria (via train)
Leg 8: Austria to Bolzano, Trentino, Italy (via car)
Leg 9: Italy to Goa, India (train to Milan, MXP>DXB>BOM>GOI)
Leg 10: India to Hong Kong, China (GOI>DEL>HKG)
Leg 11: Hong Kong to Okinawa, Japan (HKG>OKA)
Leg 12: Japan to Anchorage, Alaska, USA to Barrow (OKA>NRT>SEA>ANC, ANC>BRW)
Leg 13: Barrow to Fairbanks, Fairbanks to Las Vegas, Nevada (BRW>FAI, FAI>SEA>LAS)
Finish Line: Lake Mead National Recreational Area
5 Continents, 10 Countries (new: Lesotho)