El Palo Alto park is a .5 acre park and is the home of "El Palo Alto" the redwood tree which was the source of the the city of Palo Alto's name. The park exists to preserve this tree and the town's history. The small park has several monuments, a walking and biking path, a few historical descriptions, and the San Francisquito Creek.
El Palo Alto is a coastal redwood tree that is 110 feet tall (compared to 134.6 feet in 1951), 90 inches in diameter, and has a crown spread of 40 feet. El Palo Alto originally had twin trunks, but an 1887 flood in the San Francisquito arroyo tore off one of the two. The tree dates approximately to the year 940. The tree is California Historical Landmark No. 2 (number 1 is the custom house in Monterey). It is recognized by the National Arborist Association and International Society of Arboriculture for its historical significance as "a campsite for the Portola Expedition Party of 1769."
The plaque at the base of the tree bears the following inscription:
Under this giant redwood, the Palo Alto, November 6 to 11, 1769, camped Portola and his band on the expedition that discovered San Francisco Bay, this was the assembling point for their reconnoitering parties. Here in 1774 Padre Palou erected a cross to mark the site of a proposed mission (which later was built at Santa Clara). The celebrated Pedro Font topographical map of 1776 contained the drawing of the original double trunked tree making the Palo Alto the first official living California landmark.
A second plaque across the creek in the town of Menlo Park reads:
Portola Journey's End; November 6 - 10 1769. Near "El Palo Alto," The Tall Tree, the Portola Expedition of 63 men and 200 horses and mules camped. They had traveled from San Diego in search of Monterey, but discovered instead the Bay of San Francisco. Finding the bay too large to go around, and deciding that Monterey had been by-passed, they ended the search and returned to San Diego.