The Oaks Tavern, located at the northwest tip of the Oaks amusement park, was a feature attraction of the park when it opened in 1905, serving Weinhard's beer for five cents a bottle along with a fine dining experience, a view of the Willamette and live music.
In as little as a year, however, the temperance crusade began to move against the Tavern. In 1906 an attempt was made to designate Sellwood a dry neighborhood. The measure failed in an county election that June, but in the wake of defeat it was reveled that the Oaks' Superintendent of Construction had paid for Oaks and OWP employees to stay overnight in a Sellwood hotel, the address of which they used to register as Sellwood resident voters. Certain prominent Sellwood landowners further colluded by swearing (falsely) to the veracity of the employees' resident status. Despite a grand jury indictment booze remained king at the Oaks.
In the following year however drunkards from the Oaks managed to accomplish what democracy could not. In the remaining months of 1906 an off-duty police officer threatened an employee with his revolver, and in another incident a inebriate attempted board a moving trolley and predictably miscalculated his leap, resulting his skull being crushed beneath the steel wheels. In 1907 management declared the Oaks dry.
The Oaks attempted to lift this ban in 1908 and again in 1909, although the City refused to grant new liquor licenses. It might seem that the third try was the charm in 1910 but the reality was that new owner John Cordray's local celebrity had more to do with the Oaks' new designation as "Portland's adult playground." But the looming national nightmare of Prohibition was clearly on the horizon and in 1914 the Oaks' went dry once more. By 1916 Prohibition was law in Oregon.
I'm not sure when the Oaks' Tavern was demolished. I can't believe that the building was that structurally long-lived in the first place. The Willamette flooded to varying degrees regularly and lack of patronage due to Prohibition would probably see the Tavern torn down prior to the second world war, if not the first.