Stargate actors in Atlantises

[MS]

Although SG-1 alum Claudia Black has never appeared in the Atlantis series she did appear on Atlantis when there was a SG-1-Atlantis crossover in the SG-1 season 10 episode The Pegasus Project originally broadcast on July 28 2006. This was not the first time that Ms Black has been to a place called Atlantis based on the Greek legend.
She was in another place called Atlantis nine years earlier on May 19 1997 in the Hercules season 3 finale called….Atlantis.
Along with Claudia Black, what the Atlantis of the world of Stargate has in common with the Atlantis in the Hercules episode is that both Atlantises is not an underwater city on Earth.
Stargate Atlantis was a place at a galaxy far far away and whilst the Atlantis in the Hercules episode is on Earth it was on an island instead.

[MS]

As Jack O'Neill, Richard Dean Anderson had appeared in four episodes of Stargate Atlantis.

However this was not the first time that Anderson had appeared in a situation based on the Atlantis legend.

Before playing Jack O'Neill in SG-1, Anderson was well known for playing the title character of MacGyver and the first MacGyver TV movie was called Lost Treasure of Atlantis.