The royal couple have brought along their 4-month-old son Archie Harrison. Harry and Markle previously had a romantic safari together in Botswana, South Africa, before their marriage in May 2018.
Harry, on the trip, plans on visiting Angola, where his late mother Princess Diana famously visited in 1997 to raise awareness about the minefields that plague the area.
Markle will be using the trip to focus on female empowerment.
"You service to the causes you care so deeply for inspires me every day. You are the best husband and most amazing dad to our son. We love you," she said.