Over the course of four years a typical student at the University of Minnesota may walk dozens of miles on the Washington Avenue Bridge, the main thruway across campus. On a tree right off the bridge’s edge, hundreds of shoes from those students who walked the strip over the years are on full display, dangling from the branches of a tree.

The University of Minnesota Shoe Tree, located a few feet south of the bridge on the west bank of the Mississippi River, is a local, laced-up landmark, and nobody knows exactly why it’s there.

The first shoe is believed to have been placed on the tree about 50 years ago, and since then hundreds of shoes and even two bikes have been hung on the tree’s branches. Walking along the Washington Avenue Bridge, you can easily see ice skates, hiking boots, slippers, and signed sneakers dangling among the leaves. Beneath the bridge, mixed with the soil and litter, are hundreds of failed flings lying on the ground. 

So why would so many students launch their perfectly fine shoes onto a tree? The answer remains a mystery. Some believe that the phenomenon exists for students to celebrate losing their virginity, or more commonly, that it is a tradition for graduating seniors to hurl their shoes to leave their mark on the university. The most likely theory for the origin of the shoe tree, however, is a lot more straightforward: one day, someone randomly threw their shoes on the tree, and a bunch of other students followed suit.