Wayne Pivac head coach said on Tuesday that Wales face "probably the ultimate challenge" in tackling Rugby World Cup winners South Africa away from home at altitude.
Pivac's side, whose poor Six Nations campaign ended with a dismal home defeat against Italy three months ago, have yet to beat the Springboks in South Africa following 10 attempts.
They face Test matches in Pretoria, Bloemfontein and Cape Town beginning on July 2, with the opening two encounters being played in grounds at least 1,300m above sea level.
"In Test rugby, you want the ultimate challenge as players and coaches, and this is probably the ultimate challenge with South Africa at altitude and us coming off the back of our Six Nations and where they are at in their game," said Wales coach Pivac.
"From our point of view, it is a huge challenge. We are playing the world champions in their own back yard at altitude in the first two Tests in front of their own fans for the first time since they won the World Cup (in 2019)."
Pivac has added uncapped Scarlets prop Harri O'Connor to his tour squad, meaning that 34 players will board the plane later this week.
He allayed any fitness fears about captain Dan Biggar, who took a blow to his back during Northampton's English Premiership semi-final defeat against Leicester earlier this month.
O'Connor's selection takes the number of uncapped players to four, with fellow prop Sam Wainwright, Leicester flanker Tommy Reffell and Cardiff number eight James Ratti also in the touring party.
"There is no better learning than going up against the best in the world in any sport and at the moment you would have to say the South African scrum has probably shown it has consistently been the best in the world," Pivac said.
"Their lineout drive is superb, their forward play is probably second to none. They are not world champions for nothing.
"They are very, very good at what they do, so if you are a young guy going on tour and coming up against that, you are going to learn a lot."