Tap the game to open it fullscreen. On a computer, Esc exits; on a phone, use the ✕ button.

How to play

Four goods, four stalls in each row. Fill the empty squares so that no good repeats in any row or column. Tap an empty square, then a good (or use the arrows and the keys 1 to 4). A wrong square counts as a mistake, and the third mistake ends the game.

The story behind it

Kaupang, in Norway, was a Viking Age market near Larvik. The squares in the game are made up. Read the story in Kaupang: the Viking market of Skiringssal, in Norway, and what scales, silver and graves reveal.