Not a flat you live inside, like in the UK – but a flat piece of cardboard.
Source Appleshadow
Vector version of a png that was uploaded to Pixabay by pencilparker
Source Firkin
A background tile for web with abstract repeating texture of dark "stone wall".
Source V. Hartikainen
Remixed from a PNG that was uploaded to Pixabay by gingertea
Source Firkin
Remixed from a drawing in 'The March of Loyalty', Letitia MacClintock, 1884.
Source Firkin
Remixed from a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
To get the tile this is formed from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
This one takes you back to math class. Classic mathematic board underlay.
Source Josh Green
From a drawing in 'Worsborough; its historical associations and rural attractions', Joseph Wilkinson, 1879.
Source Firkin
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Just to prove my point, here is a slightly modified dark version.
Source Atle Mo
This ons is quite old school looking. Retro, even. I like it.
Source Arno Declercq
This is so subtle you need to bring your magnifier!
Source Carlos Valdez
Tiny, tiny 3D cubes. Reminds me of the good old pattern from k10k.
Source Etienne Rallion
Prismatic Groovy Concentric Background 4 No Black
Source GDJ
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
This reminds me of Game Cube. A nice light 3D cube pattern.
Source Sander Ottens
Not even 1kb, but very stylish. Gray thin lines.
Source Struck Axiom
Inspired by a 1930s wallpaper pattern I saw on TV.
Source Firkin
A free web background image with a seamless concrete-like texture and an Indian-red color.
Source V. Hartikainen
The image depicts the Japanese Edo pattern called "seigaiha" or "青海波" meaning "blue -sea- wave".I hope it's suitable for the summer season.
Source Yamachem
Floral patterns might not be the hottest thing right now, but you never know when you need it!
Source Lauren
A comeback for you: the popular Escheresque, now in black.
Source Patten