Bandelier, on his journey to the Upper Yaqui River, in 1885, which took him as far as Nacori, also refers to them, and Professor W.J.McGee, on his expedition in 1895, found in Northeastern Sonora ruins locally known as _Las Trincheras_, which he considered the most elaborate prehistoric work known to exist in Northwestern Mexico.

They comprise, he says, terraces, stone-walls, and inclosed fortifications, built of loose stones and nearly surrounding two buttes.
I must not omit to mention that in a week's exploration in the mountains near Nacori, Mr.Stephen and his party did not find any pottery fragments, nor flint flakes, nor grinding stones.

They reported that there was in that region no other trace of an early people than the hundreds of trincheras in the lower portions of the arroyos.
Noteworthy, however, was the frequent occurrence of old trails across the hills, some quite plainly traceable for three and four hundred yards.

Old oaks stretched their limbs across many of them quite close to the ground.
While at Nacori I learned from the inhabitants that at no great distance from their town there were several deposits containing _huesos giganteos_ (giants' bones), a name given to fossils in this part of the world, where the people imagine that the large bones were originally those of giants.

I had then neither time nor men to make excavations of any importance; but Mr.White, the mineralogist of the expedition, whom I sent to look into the matter, and who devoted a week to the examination of the deposits, reported that one of them, in a valley sixteen miles south of Nacori, was a bed of clay thirty feet thick and about a mile and a half long.