Rubuta ci gaba don wannan sakin layi - A shekara ta 1900, yawan mutanen ya kusan 900 kuma mazauna yankin sun tura Kamfanin Tamalpais Land &amp; Water Co. don tallafawa hadewa. Kungiyoyi da kungiyoyi sun haɗu da su ciki har da Outdoor Art Club (1902) (wanda Laura Lyon White ta shirya), Masonic Lodge (1903) wanda ya yi bikin cika shekaru ɗari a 2003 da Dipsea Race (1905), na biyun yana bikin cika shekaru 100 a shekarar 2010. Babban fashewar yawan jama'a na biyu ya zo ne bayan Girgizar Kasa ta 1906
Ka yi haƙuri. Duk da yake yawancin San Francisco da Marin County sun lalace, mutane da yawa sun gudu zuwa Mill Valley kuma mafi yawansu ba su bar ba. A wannan shekarar kaɗai, yawan mutanen ya ƙaru zuwa fiye da 1,000. An gina gada ko kuma an gina madatsar ruwa, an yi ƙarin hanyoyi kuma an shafa musu man fetur, kuma an zuba siminti a kan hanya. An bude makarantar sakandaren Tamalpais a shekarar 1908, an gina zauren gari na farko a shekarar 1908, kuma an gina laburaren Andrew Carnegie a shekarar 1910. Ofishin gidan waya ya buɗe a ƙarƙashin sunan "Eastland", duk da haka bayan ƙin yarda da yawa an canza shi zuwa "Mill Valley" a cikin 1904. An yi wasan kwaikwayo na farko na Dutsen a Gidan wasan kwaikwayo na Dutsen a Mt. Tam a shekarar 1913.