In around 1770 the neoclassical architect Robert Adam designed Pulteney Bridge, a three-arched bridge spanning the River Avon. He used as his prototype an original, but unused, design by Andrea Palladio for the Rialto Bridge in Venice. Adam also submitted plans for the new Assembly Rooms but these were rejected as too costly. John Wood, the Younger raised funding for the construction of the Assembly Rooms by the use of a Tontine, an investment plan that is named after the Neapolitan banker Lorenzo de Tonti, who is credited with inventing it in France in 1653. It combines features of a group annuity and a lottery. Each subscriber pays an agreed sum into the fund, and thereafter receives an annuity. As members die, their shares devolve to the other participants, and so the value of each annuity increases. On the death of the last member, the scheme is wound up. Construction started in 1769 and was completed in 1771, when a grand opening was held.