Landmark Tower Company

The prototypical Landmark tower, also known as an Adelphon tower, is a tripod in shape with three legs that rise to meet each other about a third of the way up. The legs taper down from larger footings to a thinner middle and then expand again to the point where they meet. The outer cords continue all the way up to the top of the tower in one swoop, but the inner three loop around into each other, creating a central ovoid and voided core. Aside from its unique appearance, the Landmark tower design has several advantages compared to the typical free standing lattice tower, with less wind resistance and a reduced amount of steel required for construction.[3]

The most well known example is the Star Tower, located in Cincinnati, Ohio. The individual base leg columns were erected by crane, while the upper sections of the tower were built using a Sikorsky S-64 helicopter.[4] Numerous other Landmark towers can found across the United States, including the Mesquite Tower in Mesquite, Texas, the Hughes Memorial Tower in Washington, D.C., and, at a smaller scale, WPXR-TV's analog antenna on Poor Mountain in Virginia, and another atop the Energy Plaza skyscraper in downtown Dallas, used by TXU Energy for its communications needs. None are known to have been built outside of the United States. The Landmark Tower Company went bankrupt after its owner died in 2002.[5]

• Lattice tower
• List of tallest freestanding steel structures