From the Guidebook:
William Workman and John
Rowland organized the first wagon train of permanent eastern
settlers, which arrived in Southern California on November
5, 1841. Together they owned and developed the 48,790-acre
La Puente Rancho. Workman began this adobe home in 1842
and remodeled it in 1872 to resemble a manor house in
his native England. He also established 'El Campo Santo,'
this region's earliest known private family cemetery,
in 1850, the miniature Classic Grecian mausoleum was built
in 1919 by grandson Walter P. Temple.