Sand Harbor is part of Lake Tahoe Nevada State Park on the Northeast shore. This naturally sandy area has wide beaches framed by dramatic groups of massive boulders. Despite being a state park with lots of parking lots, restrooms, and a restaurant, Sand Harbor shows many signs of previous use by the Washoe tribe. There is a great deal of information by and about the Washoe, including a downloadable booklet, at their tribal website here . The Washoe spent the summers along the shore until they were displaced by the 49ers in the gold rush.
One of the attractions of the park is a boardwalk nature trail over the sandy peninsula that points west.
Not far from this is a large boulder with two or three prominent grinding scrapes.
It is well known that there are many mortars and slicks along Lake Tahoe. However, there is no mention of propped boulders.
When I visited the park, I sat on a bench to watch some daredevils jumping from the boulders in the first picture. I noticed a large pine cone resting in a small depression on top of a boulder near a lifeguard chair.
When I investigated, I found a perfectly round mortar about 8 inches across and 2 inches deep.
Here is the propped boulder I showed last week. It is along the shoreline south of the boat launch.
The foot has a somewhat concave shape, perhaps from centuries of water erosion.
And here is another possible propped boulder in the center of the photo.
Note that there are three apparent propped boulders at this site. This is consistent with the "corners" of three propped boulders I have noted in RI. There are also mortars and grinding scrapes in this site, indicating this was a campsite.Undoubtedly much more was lost when the park was developed.
There are also a couple of stone rows in a sandy space between the boulders.
Perhaps it was once the base of some sort of fish weir. The stains on the boulders indicate the lake is often higher.
Standing in water at the boat launch are five monumentally large cairns.
These show clearly in satellite imagery. There are three in a row under the Lake Tahoe caption, and two to the left, with a boat pointing towards them.
Note how the lake bottom around the three cairns is free of rocks. These cairns were probably created by channel clearing for the boat launch. So many details in a small, heavily utilized state park!