Most mooring places in Venice are given in concession to private or commercial users by the Magistrato delle Acque, the magistrate of the waters, and they’re not supposed to be used by any others. This is not always respected, and the concessionary of this space have had enough of free riders.
The sign reads: “Don’t moor (here), or at my return I will untie your boats, leaving it to its destiny. Tired of moving boats. Concession N. XXXX”
Seen in Rio di S. Severo, May 17th, 2009.