The impossible triangle was first painted in 1934 by swedish painter Oscar Reutersvдrd. He drew his version of a triangle as a set of cubes in parallel projection. Although, many painters later used the impossible triangle in their art, Oscar Reutersvдrd did open the fantastic world of impossible figures. He created thousands of impossible figures for his life and now he is known as “father” of impossible figures. In 1980 the Swedish goverment decided to place his impossible triangle and two other his figures on postage stamps, which were printed for about two years.
But the shape of impossible triangle is also well known as a Penrose tribar. In 1954 english mathematician Roger Penrose first drew the impossible triangle in it’s common view. Unlike Reutersvдrd’s triangle, he painted the triangle as three bars connected with right angles. He gave perspective effect to it, which increased effect of impossibility. He published his version in the British Psychology Magazine in 1954 in a joint article with his father Lionel Penrose.
Penrose sent a copy of the article to M.C. Escher and in 1961 he created the famous lithograph “Waterfall”. Impossible triangles have appeared many times in numerous artworks since that time. Although it is impossible to construct, it is possible to create three-dimensional objects that looks impossible from a single point of view and looks ordinary from all other points of view. An impressive example is the 13-metre high sculpture of the impossible triangle created in Perth (Australia).
Edited from the excellent Impossible World Website