Mile High Club

The Mile High Club is a tower complex currently under construction in Downtown Los Santos, featured in Grand Theft Auto V. Its completion date is unknown.

Once completed, it is planned for this building to be the tallest structure in all of Los Santos.

The term "Mile High Club" is a slang term applied collectively to individuals who have sex while on board an aircraft in flight. It also appears to be a reference to the Kingdom Tower, formerly called the "Mile High Tower", a skyscraper under construction in Saudi Arabia who is announced to reach a mile in height.

Mile High Club in GTA San Andreas
A similar-looking building also under construction appears in Grand Theft Auto: San Andreas. It is however unknown if it is the same building.

Trivia:
The Mile High Club could be based on the Wilshire Grand Towers complex in los angeles, stated to be the tallest building in real life as well.