A small landscaped park on the original site of the Martin Murphy Jr. Mansion — the 1850 prefabricated wooden house that founded the city. The mansion itself, the oldest wood-frame house in California, was tragically destroyed by arson in 1961; the park preserves the location and includes interpretive panels about Murphy and the Donner-Reed party (the Murphy family came west with them in 1844).
Combine with a visit to the Sunnyvale Heritage Park Museum a few blocks away, which holds the surviving artefacts from the mansion.