The PPIE was the 1915 wolds fair, it was a pivotal moment for San Francisco a city that had been almost completely destroyed by earthquake less than 10 years before. The event was a huge success boosting the morale of the entire bay area and helping one of Americas great cities get back on her feet.
The city chose to instead of hosting the fair in golden gate park, to fill in the mud flats and create one of modern day San Francisco's priemer neighborhoods the Marina. The grounds comprised of more than 600 acres between the Presido and Van Ness and fronted the bay itself, and took more than four years to complete. The fair ran from Feb 230th to dec 4th of 1915 and was considered a great success.
Here is an excellent site that goes over a little of the history, art and memorabilia of the expo.
In 1915 my Great Great grandparents took a trip to San Francisco
The inside cover of the sovenieer booklet mailed to my Great Grandmother Florence May Bishop
The Council of architects adopted a general plan that was as bold as it has proven successfull. The units are not individual buildings, but beautiful courts with intervening asiles and continuous facades, and around these are interwoven eight great exhibit palaces surmounted by the tower of jewels, 433 feet high. These are flanked on the east by the huge palace of machinert and on the west by the buitiful fine arts palace, while still further west the various buildings of the states of the union and the pavillions of foreign nations are cleverly and effectively grouped. At the eastern extremeity, screened by the machinery palace, is the most wonderfull and extensive amusement section ever planned at any exposition. The great south gardens extend for 3000 feet along the south front of the main groups of exhibit palaces, and at the western end is the magnificent palace of horticulture, while waters of San Francisco bay, facing the Marin hills on the opposit side, with mount Tamalpais a few miles beyond. Symmetry, balance and harmony are the keynotes to the exposition, and these have found expression not only in architectural construction, but in decroative form, in a woinderfull color scheme and i na marvelous lighting arrangement that has never previously been equalled. It is estimated that more than $50,000,000 had been ecpended on the exposition.
(Keep in mind $50,000,000 in 1915 would equal $1,085,044,554.46 today with an average inflation of 3.86%)
Look Closely, these are colorized photographs not paintings.
Sadly the buildings were made to be temporary structures many being made with a simple wood frame then covered with a material called "Staff" that could not survive much more than a single year, and was made of a combination of burlap and plaster - It was cheap and easy to mold. The only surving building that I am aware of is the Palace of Fine Arts, home to the Exploratorium one of the best hands on science museums in the world!
Every where were gardens, 1500 sculptures and murals, 30,000 imported plants and over 70,000 rhododendrons. The gardens were designed by the same landscape architect as Golden Gate Park John McLaren
Lighting also played a large role in how the Expo was viewed. GE designed the basic scheem susing thousands of colored spotlights, hidden well and made to make the buildings sparkle and glow. Also The entire area was illuminated by indirect lighting by General Electric. The "Scintillator," a battery of searchlights on a barge in the Bay, beamed 48 lights in seven colors across San Francisco's fog banks. If the fog wasn't in -- no problem: A steam locomotive was available to generate artificial fog.