Saturday, July 29, 1769
To north of Fullerton.

Gaspar de Portolá Diary
The 29th, we proceeded for three hours on a good road. Much pasture, but water sufficient only for the men. Here there was an Indian village of about fifty inhabitants.

Miguel Costansó Diary
At two o'clock in the afternoon, we started from the Río de los Temblores. We travelled for two leagues, leaving the level country and the coast to enter the mountains, as we feared a lack of water in the plain. We found no water for the animals, but there was sufficient for the people in some little springs or small pools in a narrow canyon close to a native village. The Indians of this village were holding a feast and dance, to which they had invited their neighbors of the Río de los Temblores.

Fray Juan Crespi Diary
At two in the afternoon we set out from this place and crossed the river with great difficulty, on account of the swiftness of its current, and followed the plain to the northwest. Near the river the mountains have many prickly pears and much sage, but afterwards all the land continues fertile and is well covered with good grass. After traveling a short distance we turned to the north-northwest, and after marching a league and a half we again turned to the northwest, in order to ascend the nearest mountain range, which was now very low and comes to an end to the west-northwest. We climbed a medium-sized hill, quite steep, and descended to a very green little valley, which has a small pool of water, on whose bank there is a very large village of very friendly heathen. We made camp on a hill near the pool which has good grass for pasture. As soon as we arrived the whole village, which numbered more than seventy souls, came to visit us. They invited us to go to stay at the village, but, in order not to be incommoded we remained on the hill, at the foot of which there is a beautiful valley of many leagues of good land. But the place has no water except the pool, which was only enough for the people, for which reason the animals were left without drinking. This afternoon's march occupied two hours, during which we traveled about two leagues. The place was known by the name of Santa Marta.(1) The Indians of this village were having a feast and dance, to which they had invited their neighbors of the river called Jesus de los Temblores.

(1) Bolton called this place "La Brea Canyon", but there's not actually a place with that name. On the other hand, there are two places along Brea Creek named "Brea Canyon". Given the general direction of Portola's travel, and the description in Crespi's diary, the "nearest mountain range" would have been the hills now called "Sunny Hills", or "Coyote Hills" (east and west). Crespi doesn't mention a creek near the camping place, just a "small pool of water". That could have been at what is now redundantly called "Laguna Lake", on the north side of the hills, facing La Habra.

July 28 To Santa Ana River, near Olive.
July 30 To or near Bassett, on the San Gabriel River