Seascape near Les Saintes-Maries-de-la-Mer, 1888 by Vincent van Gogh

In his letter to Theo dated on June 4, 1888, Van Gogh Wrote:

At last, I'm writing to you from Saintes-Maries on the shore of the Mediterranean. The Mediterranean has a color like that of mackerel, by which I mean it's always changing. You can't even tell if it's blue because a second later the changing light has taken on a pink or gray tinge.

I went for a walk by sea one night along a deserted beach. It wasn't very cheery but neither was it sad it was beautiful. The deep blue of the sky was dotted with clouds of a deeper blue than the essential blue of intense cobalt, with others of a brighter blue, like the blue whiteness of the Milky Way. In the blue depths, stars sparkled brightly, greenish, yellow, white, pink, brighter still, more brilliant and more like precious stones than at home or even in Paris like opals, emeralds, lapis, rubies, and sapphires, one might say.

The sea was a very deep ultramarine the shore, it seemed to me, a kind of violet and pale russet tone and on the dunes (which are about sixteen feet [five meters] high) Prussian blue bushes.