Venice glossary: lagoon, tide, transport and open data
The terms you meet on the map and in official sources, briefly explained.
- Acqua alta (high water)
- A tide above ordinary levels that floods part of the city. In Venice it starts indicatively at +80 cm above the Punta della Salute tide datum.
- Punta della Salute tide datum (ZMPS)
- Reference level for Venice tides: mean sea level measured at Punta della Salute in 1897. “+110 cm” means 110 cm above this datum, not 110 cm of water in the street.
- Sustained, very sustained, exceptional tide
- Categories used by the City of Venice Tide Centre: sustained from +80 cm, very sustained from +110 cm, exceptional from +140 cm.
- Tide Centre (CPSM)
- The City of Venice Tide Forecasting and Warning Centre: it measures the tide, issues forecasts and sounds the sirens. Its data is published as open data on dati.venezia.it.
- Sirens
- Audible warning across the city when a tide of +110 cm is forecast: one tone for +110 cm and one more every 10 cm, up to four tones from +140 cm.
- MOSE
- System of mobile gates at the three lagoon inlets (Lido, Malamocco, Chioggia) that, when raised, temporarily separate the lagoon from the sea during the highest tides.
- Lagoon inlets (bocche di porto)
- The three openings between the barrier islands that connect the lagoon to the Adriatic Sea: Lido, Malamocco and Chioggia.
- Passerelle (raised walkways)
- Elevated pedestrian walkways set up by the City on the main routes during high water. The plan states at which tide level each route is installed.
- Sestiere
- Each of the six historic districts of the centre: Cannaregio, Castello, Dorsoduro, San Marco, San Polo and Santa Croce. Giudecca belongs to Dorsoduro.
- Venetian house numbers
- In the historic centre numbers run across the whole district, not by street: an address like “Cannaregio 3450” gives the district and number, without the street name.
- Calle, fondamenta, campo, rio
- A calle is a pedestrian street; a fondamenta a street along a canal; a campo a square (the only “piazza” is San Marco); a rio a minor canal.
- Vaporetto and motoscafo
- ACTV's public transport boats in the city and the lagoon. ACTV's GTFS tells the vehicle types apart.
- Traghetto (gondola ferry)
- A gondola that crosses the Grand Canal from one bank to the other at a few fixed points, handy where there are no bridges.
- Pontile (waterbus stop)
- The floating waterbus stop. A stop can have several berths marked with letters (A, B, C…).
- Alilaguna
- Private water transport company linking Marco Polo Airport with Venice, Murano and the Lido.
- People Mover
- Automated cable shuttle linking Tronchetto, Marittima (cruise terminal) and Piazzale Roma.
- GTFS and GTFS-Realtime
- Open formats for public transport timetables (GTFS) and live positions and delays (GTFS-Realtime). ACTV publishes them as open data and VOD uses them for waterbuses and buses.
- Open data
- Data published under a licence that lets anyone reuse it, commercially too, on the licence's terms.
- CC BY and ODbL
- Common open licences. CC BY asks you to credit the source; ODbL (used by OpenStreetMap) also asks you to share derived databases under the same licence.