Construction began on the tower on September 6, 1961 while a line of store-front units called Landmark Plaza and a small 120 unit apartment complex was being completed on the site for a November 1st opening. With parking for 650 cars and the first strip department store, Ramsays, Landmark became the talk of the town. The tower was set to open in 1963.
To construct the tower, Caroll chose a proprietary method of slip forming concrete construction developed by the MacDonald Engineering Company of Chicago and subcontracted them to build the main pillar which the top dome would sit on. William Macafee, a Vice President with MacDonald, supervised the project.
Due to Clark County gaming regulations, gambling was not allowed above the first floor of a casino. On March 12, 1962, Caroll was successful in getting the County Commissioner to lift the ban which allowed him to put a casino on the 29th floor of the Landmark Tower. In December, Caroll ran out of funding. His creditors refused to loan him any additional money to complete the tower and work halted. The tower sat 80% complete - an empty shell which, due to it's contrasting geodesic shapes, appeared to lean to the side no matter what angle you viewed it from. The tower was, in fact, straight. This caused residents to call it "The Leaning Tower of Las Vegas" and "Frank's Folly". It can be seen in this stage behind Elvis Presley in "Viva Las Vegas".
In 1966, Caroll brought in additional partners and formed Plaza Tower, Inc. in order to complete the tower. After four years of dormancy, the Teamsters Union Pension Fund awarded Caroll $5.5 million to complete the Landmark. Work resumed on August 22, 1966 after Louis P. Scherer's Fremont Construction Company was awarded a $2.5 million contract to complete the tower. Scherer was one of the Plaza Tower, Inc. partners. The tower was completed by early 1967 and was set to open on September 15, 1967 but that was soon changed to November 15. Landmark then announced the opening of its main showroom and lounges on New Year's Eve, 1967 but due to lack of funding it didn't happen. Because of this, several slot tokens can be found dated 1967 even though the hotel had not yet opened. Caroll expected to have the hotel open in April of 1968, however he dropped his request for a gaming license due to an assault and battery charge, which was eventually dropped.
Plaza Tower, Inc. entered involuntary bankruptcy proceedings in 1968 with nearly 120 creditors totaling $5.8 million. In October of 1968, reclusive billionaire Howard Hughes offered to purchase the Landmark for $17.3 million and agreed to pay off the creditors. Hughes already had a vast Vegas empire including the Desert Inn, Silver Slipper, Sands, Frontier, and the Castaways. Rumors claim that Hughes simply wished to see the project finished, as he disliked "loose ends". Other hotels, almost all of them mob controlled, contested Hughes' purchase of the Landmark on the grounds that it would give him a monopoly on the casino business in town. The court sided with Hughes and granted him the sale on January 19, 1969.