According to the LA Almanac, that took place in 1891, when President Benjamin Harrison visited Pasadena.
Who the heck was he?
Wiki to the rescue. Benjamin Harrison (we must use his first name as there have been TWO President Harrisons in our history, neither very effective) was a one-term wonder from Indiana. A Republican, his administration is best known for passing the Sherman Antitrust Act--the piece of legislation that was supposed to break up monopolies and did, in fact, break the American Tobacco Company into several smaller corporations (one being R. J. Reynolds...so smaller is a relative term.) And his budget was the first to reach One Billion Dollars! That probably lost him re-election.
Here is his carriage, with him in it, in front of the Los Angeles House in Pasadena--a photo held by the Los Angeles Library.
So, what about his visit? It was part of a month-long speechifying tour of the Pacific Coast (here's a map, courtesy of the Smithsonian).
At 7:05 pm on April 23, 1891, against a background of ringing church bells, cannon fire, and cheering throngs--as well as bonfires near the tracks--a special train brought the prez, his family, and two cabinet members to Pasadena for a party at the Hotel Green, in apartments "profusely decorated with flowers." Visitors--which could include anyone, apparently--came in through the front of the hotel and exited along Raymond. The president received them under an arch trimmed with evergreen and lilies.
Ladies, however, were directed to the hotel ballroom, where Pasadena matrons had prepared refreshments, and where the Los Angeles Mandolin Club provided music. The evening closed with an 'invitation only' dinner at 10, with a cake iced and shaped like the Capital. "Hail to the chief" was spelled out in flowers on one wall.
The Hotel Green is now the Castle Green, btw. They have a great history album of old photos, one being the pre-1903 picture at the top of this post.
The next morning, the presidential party traveled (by carriage driven by--I quote directly from the Times--"four spanking horses") along Colorado to Marengo, then south to California, east to Moline, and to the Mayor's house. After that the route went: Walnut to Raymond to Colorado to Fair Oaks to Orange Grove to Arroyo to Colorado Court to Orange Grove to California to Pasadena to Bellfontaine to Orange Grove to Columbia to the Raymond Hotel. Not done! Then Columbia to Orange Grove to Colorado ("through Mrs. Carr's grounds") back to Colorado to Raymond.
The route was announced so that a good crowd would turn out and make the city proud. Different times, huh?
From Pasadena the president journeyed to San Diego, staying at the Hotel Coronado.