Why did Capitol Hill become the center of gay life in Seattle?

Back before Capitol Hill became the center of gay life in Seattle, most of the American public thought of homosexuality as not only illegal but even dangerous.  

Consequently, gay culture was underground. Gay bars were confined to the red light district and in Seattle, that used to mean Pioneer Square.

But in the cultural shifts of the 1970s, gay people were ready to leave the red light district and Capitol Hill looked like the right place at the right time.

But why Capitol Hill?

Read more on I Wonder Why ... ?