Not a flat you live inside, like in the UK – but a flat piece of cardboard.
Source Appleshadow
Dark blue concrete wall with some small dust spots.
Source Atle Mo
A bit strange this one, but nice at the same time.
Source Diogo Silva
This was formed by distorting an image of a background on Pixabay.
Source Firkin
From a drawing in 'Hubert Montreuil, or the Huguenot and the Dragoon', Francisca Ouvry, 1873.
Source Firkin
Dark, lines, noise, tactile. You get the drift.
Source Anatoli Nicolae
From a drawing in 'Resa i Afrika, genom Angola, Ovampo och Damaraland', P. Moller, 1899.
Source Firkin
You guessed it – looks a bit like cloth.
Source Peax Webdesign
Vertical lines with a bumpy, yet crisp, feel to it.
Source Raasa
Prismatic Hypnotic Pattern 2 No Background
Source GDJ
A dark background pattern/texture of a dimpled metal plate.
Source V. Hartikainen
I’m starting to think I have a concrete wall fetish.
Source Atle Mo
Prismatic Abstract Geometric Background derived from an image on Pixabay.
Source GDJ
Number 4 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
A free web background image with a seamless concrete-like texture and an Indian-red color.
Source V. Hartikainen
If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117
Source Viscious-Speed
Remixed from a raster on Pixabay that was uploaded by ArtsyBee.
Source Firkin
Redrawn based on a drawing in 'По Сѣверо-Западу Россіи' Konstantin Sluchevsky, 1897.
Source Firkin
Wild Oliva or Oliva Wilde? Darker than the others, sort of a medium dark pattern.
Source Badhon Ebrahim
From a drawing in 'Hyde Park from Domesday-Book to date', John Ashton, 1896.
Source Firkin
A smooth mid-tone gray, or low contrast if you will, linen pattern.
Source Jordan Pittman
Seamless Dark Grunge Texture. Here's a new grunge texture for use as a background.
Source V. Hartikainen
From a drawing in 'Uit de geschiedenis der Heilige Stede te Amsterdam', Yohannes Sterck, 1898.
Source Firkin
From a drawing in 'Resa i Afrika, genom Angola, Ovampo och Damaraland', P. Moller, 1899.
Source Firkin