The two twelve-story south wings of the hotel were built in 1904, and the double-width north wing was completed in 1913, initially as apartments for permanent guests. With its acquisition by Western Hotels, the hotel was changed from a home of elderly San Francisco socialites, some of whom lived in large suites in the hotel, to a modern hotel focusing on tourism and especially conventions. The old Mural Room, decorated by Albert Herter in 1913 with seven murals comprising The Pageant of Nations, a banquet and ballroom which had hosted many of America's famous big bands, was replaced in 1970 by a six hundred room tower, designed to help the St. Francis compete with The Fairmont, its rival on nearby Nob Hill. Architect William Pereira designed the new building which was completed in 1972. The murals were rolled up and removed to storage.The St. Francis became the hotel where Republican presidents stayed when in San Francisco, while Democratic presidents usually stayed at the Fairmont. President Gerald Ford was almost shot while leaving the hotel in September 1975 by a woman named Sara Jane Moore. A former Marine named Oliver Sipple moved her hand so that Ford was not hit. Taken fom Wikipedia.
It is widely known that the Zodiac Killer made two phone calls to police: the first was received by police dispatcher Nancy Slover after the murder of Darlene Ferrin and attempted murder of Michael Mageau at Blue Rock Springs Park on July 4th 1969, with the killer stating "I wish to report a double murder. If you will go one mile east. On Columbus Parkway to a public park, you will find the kids in a brown car. They have been shot by a 9 mm Luger. I also killed those kids last year.... Good-bye". The second call was received by Officer Dave Slaight, who took the call after the double stabbing at Lake Berryessa on September 27th 1969 and heard the killer utter these words: "I want to report a murder, no, a double murder. They are two miles north of Park Headquarters. They were in a white Volkswagen Karmann Ghia", and after a brief pause uttered the words "I'm the one that did it". But there may have been a third phone call from the Zodiac Killer prior to the murder of Paul Stine. This is the phone call in which the Zodiac Killer ordered the taxicab prior to its fateful journey.
It seemed strange that Paul Stine upon approaching the San Francisco theater district and receiving a dispatch from the assistant traffic manager of the Yellow Cab Co, Leroy Sweet, to pick up a scheduled fare from 500 9th Avenue, he would then stop and pick up a random fare from the St. Francis Hotel. A random passenger flagging down a taxicab could in all probability have wanted to go anywhere, either north, south, east or west, so stopping your taxicab on the off chance he wanted to go somewhere near to your scheduled destination of 500 9th Avenue, just over three miles away, seems an unlikely scenario.
There is a possibility that Paul Stine had just picked up the Zodiac Killer as the 500 9th Avenue dispatch was offered to him from outside the St. Francis Hotel, and therefore Paul Stine, knowing that his current fare had requested Washington & Maple as a destination, was able to accept the request from Leroy Sweet.
The Harvey Hines report seems to suggest that the Zodiac Killer did order a taxicab from a public payphone at Union Square near to the St. Francis Hotel on the night of October 11th 1969.
"In looking at an area map of San Francisco, I found 217 Eddy Street appeared to only be two to three blocks from where Paul Stine picked up the Zodiac on October 11, 1969. I then called Inspector Dave Toschi at the SFPD and got more details on the Stine Killing. Toschi said that they had determined that the killer had called for a cab using the public payphone located at Union Square. Toschi said the cab then picked the killer up and drove to the corner of Washington and Cherry Streets."
This could have been the Zodiac Killer's third phone call.