The weekend before Memorial Day of 2023, I took a trip to Washington DC. On the morning of the 25th, I made my way to Arlington National Cemetery as there are a lot of justice burials there (as well as a couple presidents).
There is a cluster of justice graves located together in a spot near the main entrance. Holmes and Douglas are located to the left and over a hill behind this grouping, headed in the direction of the John F Kennedy monument.