Here’s what John Muir had to say on this topic (in January 1913):
At the National Parks conference in Yosemite Valley last October, called by the Honorable Secretary of the Interior, comparatively little of importance was considered. The great question was, "Shall automobiles be allowed to enter Yosemite?" It overshadowed all others, and a prodigious lot of gaseous commercial eloquence was spent upon it by auto-club delegates from near and far.
The principal objection urged against the puffing machines was that on the steep Yosemite grades they would cause serious accidents. The machine men roared in reply that far fewer park-going people would be killed or wounded by the auto-way than by the old prehistoric wagon-way. All signs indicate automobile victory, and doubtless, under certain precautionary restrictions, these useful, progressive, blunt-nosed mechanical beetles will hereafter be allowed to puff their way into all the parks and mingle their gas-breath with the breath of the pines and waterfalls, and, from the mountaineer's standpoint, with but little harm or good.
That said, the Department of the Interior enacted strict regulations. For instance:
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- Cars could only enter Yosemite Valley from 10 am to 1 pm or 4 pm to 5:30 pm and could only leave the Valley from 6 am to 7:30 am.
- Cars were strictly timed (to the minute!) to ensure they weren’t speeding. Violators were forced to park and wait until the next time the road was open for departures, then forced to leave Yosemite.
- Upon arrival in Yosemite Valley, all cars were required to be parked immediately at a designated location and left there until departing the Valley.