Rio sunset sail, the bay at dusk.

A Rio sunset sail is the simplest way to see the city from the water while the light changes. Our featured sail takes 3 hours, sets off from pier A2 in Marina da Gloria and caps the shared group at 12 people, with a private option for those who want the boat to themselves. A crew member in a white shirt meets you at the marina security gate and walks you down to the boat.

From there the route is set by the bay. After 40 minutes of open bay comes a pause of 15 minutes beneath Sugarloaf, then half an hour by the Santa Cruz walls, swim optional, and a photo halt at Boa Viagem Island near Niteroi. On the way home you get 25 minutes of bay views and 10 minutes by the runway of Santos Dumont Airport, where planes drop in low over the water.

Drinks and snacks come with the ticket: caipirinhas, cold beer and a sparkling white are all on the list. The live guide speaks English, Portuguese and Spanish, so the stories of the forts and the city reach everyone on deck. A seat starts from $57 per person, refundable in full if you pull out a day before.

The sail heads for the narrow mouth of the bay, where the city once defended itself from the sea. The listing names the forts of Sao Jose, Lage and Santa Cruz along the way. Riotur dates the walls of the Santa Cruz da Barra fortress, guarding the bay entrance, to 1555, built from stone cut and laid by hand, with 45 cannons inside. IPHAN, the national heritage institute, puts the start of building later, in 1578.

Across the water lies Niteroi, the city facing Rio. The boat lingers for 30 minutes of photos at Boa Viagem Island, a small green island tied to the shore. Above it, on the Mirante da Boa Viagem, sits the white saucer of the Niteroi Museum of Contemporary Art, designed by Oscar Niemeyer, which the boat passes on its route.

Coming back, the boat runs along the Aterro do Flamengo, the long waterfront park that stretches from Santos Dumont Airport to the start of Botafogo beach. The last stop of 10 minutes is by the airport runway, close enough to watch the planes come in over the water before you return to the marina. It is a surprisingly fun finale, especially for children.

Rio sails all year, but the seasons change the evening. According to Riotur, December through March is the wet season, with frequent rain and high humidity. Alerta Rio, the city weather service, adds that summer showers tend to be short and heavy, mainly in the afternoon. Those months bring warm water for the swim stop and big, dramatic skies at sunset, with towering clouds catching the last of the light.

June through September is the drier, fresher stretch of the year. The air is often clearer and the evenings fresher on the water, so this is the time to pack a warm layer. The months between the two seasons mix both moods, and any of them can deliver a fine sunset over the western hills.

Whatever the month, the crew watches the weather. The listing says the itinerary can change with the conditions or at the captain's decision. A gloomy forecast is no disaster either: cancel with a day to spare and you are refunded, free to try a brighter evening. Summer showers are often short, so look at the forecast again before you cancel.