Venus and Serena Williams, who boast six Wimbledon titles between them, will clash for the third time in an All England Club final on Saturday.
Venus, the four-time winner and defending champion, booked her place with a 6-1, 7-6 (7/3) win over Russian fifth seed Elena Dementieva to reach her seventh singles final.
Serena, the younger of the two sisters, then ended wildcard Zheng Jie's hopes of becoming the first Chinese player to reach a Grand Slam final with a battling 6-2, 7-6 (7/5) win.
The 26-year-old Serena will be looking to complete a hat-trick of Wimbledon wins over her sister having come out on top in the 2002 and 2003 finals.
Venus inists the final will be fully competitive despite scepticism in the past over whether the two perform to the maximum of their ability when they share the same court.
"I find the question pretty offensive because I'm extremely professional in everything that I do on and off the court," said Venus, the holder of six Grand Slam titles.
"I contribute my best in my sport, and I also have a ton of respect for myself and my family. So any mention of that is extremely disrespectful for who I am and my family."
Serena, 11 kilos heavier and more than 11cm taller than Zheng, had too much brawn for the world 133, who had made her mark by knocking out top seed Ana Ivanovic in the third round.
"She pushed me and really played a great match," said Serena of an opponent she had comfortably defeated in the first round here four years ago.
Zheng was left to regret a great opportunity to take the semifinal to a decider when she held set point in the 10th game of the second set but Williams was able to call on her powerful smash to rescue herself.
"She played like she had nothing to lose. I was able to hit a smash on that set point. I didn't really want to go into a third set," added the American sixth seed who will be facing her sister in a seventh Grand Slam final.
"I'm looking forward to playing Venus in the final. She'll be the toughest opponent I have faced.
"We haven't played each other in a Grand Slam final for five years but that's because our rankings fell or we were in the same side of the draw. I guess this is a new start for both of us."
Serena's last Wimbledon final appearance was in 2004, when she lost to a teenage Maria Sharapova.