The tour du coin (or tour de la conférence) was one of the corner towers of the ancient wall of Philip II Augustus in Paris, built between 1190 and 1209.

This is one of the four main towers of the wall that protected the city against attacks from the river Seine.

It stood at the corner of the downstream side of the river (i.e. the west side of the wall) on the right bank, opposite to the Tour de Nesle on the left bank, approximately at the current location of the Pont des Arts.

Upstream of the city and on each side of the river, the Tour Barbeau [fr] (right bank) and the Château de la Tournelle (left bank) had the same goal.

The tour du coin remained necessary to prevent incursions of boats with the chains drawn through the river up to the Tour de Nesle on the left bank.