The hotel debuted with 100 rooms, but the casino itself was reportedly run by managers from the Desert Inn. That stopped a few years in after proving "unsuccessful." New management introduced .49 cent breakfast specials and, in 1959, a bowling alley was added as well. By 1979, the alley had grown to 106 lanes, "making it the nation's third largest."
As the years went on, a 19-story hotel tower was added. The first nine floors opened in 1973 and the rest of the 500 rooms came online three years later. In the early 80s, more changes came to the 'boat:
...a large unused space on the second floor was converted into the Showboat Sports Pavilion, which hosted American Wrestling Association events and Los Angeles Thunderbirds roller derby matches, and competed with Caesars Palace to book high-profile boxing matches. The Pavilion was later converted into a bingo hall.
When the 90s came along so did the rise of the mega-resorts on the Strip and Showboat's popularity waned. Wikipedia reports that, in 1998, Harrah's Entertainment purchased parent company Showboat Inc. for $1.15 billion. It sold the property two years later to VSS Enterprises for $23.5 million. However, Harrah's didn't sell the name so the hotel-casino was renamed The Castaways.
The new owners never did well and according to the Associated Press, the facility was crippled by a downturn in tourism that occurred in the wake of the September 11, 2001 attacks. Discussions were held in 2002 to rebrand the property as a Holiday Inn and start a $57 million renovation and expansion, but these plans did not come to fruition.
Instead, money woes, foreclosure proceedings and bankruptcy ensued. In January 2004, Vestin, a mortgage company, took possession of the casino and shut it down. Vestin had planned to sell the property to MGI Group for $21.6 million, but Station Casinos talked (read: paid) their way into the deal instead.
In 2005, Station Casinos began to demolition the property after discovering "construction quality problems." In January 2006, the hotel tower was brought down to make way for a $90 million concept dubbed Castaways Station:
That idea ended up sinking, though, and, in 2009, Station Casinos put the empty lot up for sale for $39.5 million dollars. The property, located at Fremont and Boulder Highway, still sits unused to this day.