Starting with this episode, the "Star Trek: Enterprise" production crew established an annual tradition of featuring crew members from the real-life aircraft carrier USS Enterprise (CVN-65) in cameo roles. This next happened in First Flight (2003). As a courtesy, advance copies of first season episodes were sent to the carrier.
Robert S. Pickering, Sara Elizabeth Pizzo, and Timothy J. Whittington, visiting sailors from the real-life USS Enterprise (CVN-65), play engineering officers aboard the USS Enterprise (NX-01).
Xanadu is a legendary paradise-like capital of China, similar to the British legend of Camelot. Although Tucker claims that Xanadu is not a real place while playing Geography, an Australia-sized area on Titan (a Saturn moon), notable for being highly reflective, is actually named Xanadu. This name may have fallen out of use by the 22nd century, or Trip is not aware of its existence. There is also a historical site in China that has two names, one Shangdu, the other Xanadu.
Hoshi Sato and T'Pol have a conversation that foreshadows the Prime Directive.
The sport of geskana seems very similar to lacrosse, a sport that originated from the indigenous peoples of North America and has been adapted by European settlers.