The most westerly headland south of the Golden Gate is San Pedro Point, and the prominent headland farther south is Pescadero Point. The whole of San Francisco Bay is visible from Mount Tamalpais, except a few sheltered nooks and portions behind islands. [Illustration: VICINITY OF THE GOLDEN GATE.] The tidal area inside the Golden Gate is about seven hundred and forty square miles at high tide; this includes that portion which extends east of the Coast Range into the valley of California, and known as Suisun Bay; this bay is connected with San Francisco Bay through the Straits of Carquinez and San Pablo Bay. Emptying into Suisun Bay at its easterly end are the Sacramento and San Joaquin Rivers. Thus the tidal waters washing the base of Mount Tamalpais are connected with the interior valley of California, and tributary to them are about twelve hundred miles of navigable channels, tapping the central part of the State. From the summit of this peak the eye sweeps the horizon of the Pacific Ocean for nearly one hundred and fifty degrees. To the northwest, north, and northeast lie Petaluma, Santa Rosa, Sonoma, and Napa Valleys, the view over these being bounded by the ridges inclosing them. To the east are the Straits of Carquinez, the outlet of the fifty-eight thousand square miles of drainage of the Sacramento and San Joaquin Rivers, and the only water gap in the entire perimeter. From the east to the south lie the slopes of the Contra Costa Hills and the ranges bounding the drainage into the Bay of San Francisco, and including the Santa Clara Valley, thus embracing a magnificent view of the garden spots of California, and the cities and towns around the bay--the homes of about one third the population of the State. Three prominent peaks mark the limits of the land view: Mount Hamilton, the site of the Lick Observatory of the University of California; Mount Diablo, the base and meridian of the United States land surveys of central California; and Mount St. Helena, a volcanic peak the summit of which is common to Napa, Sonoma, and Lake Counties, and whose spurs are noted for their quicksilver mines, mineral and hot springs. [Illustration: MAP SHOWING LOCATION OF RAILROAD FROM MILL VALLEY TO SUMMIT OF MOUNT TAMALPAIS.]