Boats instead of buses, no traffic anywhere, and glass being blown — Venice suits children better than expected.
Vaporetto line 1
The slow boat down the Grand Canal, front seats if you can get them. Forty minutes end to end, and better than any tour. Any age.
Murano glass furnaces
Glass-blowing demonstrations run through the mornings on Murano, twenty minutes away by boat. The furnaces are hot and the museum is short. Ages 5+.
Palazzo Ducale
Book the palace with the Bridge of Sighs and the cells beyond it — the prisons are the part children remember. An hour and a half; ages 7+.
Lido beach
Fifteen minutes by vaporetto to proper sand and shallow water, with hire loungers and free sections at both ends. June to September; any age.
Bridges and buggies
Around four hundred bridges, nearly all stepped — a carrier is the only sane option with a baby. Transit passes are needed from age six.