On April 29, 1994, Tom Moumblow and Peter Doggett day-hiked the BIG THREE in less than 12 hours. By starting at 5 am and hiking Santa Cruz Pk first, we were able to beat the heat. After summiting Santa Cruz Pk at 9:30 am, we reached San Rafael & McKinley Mts at 12:45 pm and 1:43 pm respectively.
Even though the entire trip covers about 33 miles & 6,600 feet of gain, we feel that hiking all three in one day (starting and finishing at Cachuma Saddle) is preferable. As long as you start around 5 am and can average 3.0 MPH on a dirt road, one should be able to do Santa Cruz and get back to the saddle between San Rafael & McKinley before noon. Good luck!