North Sea Jazz Festival, July
Rotterdam Architecture Month, June
Rotterdam Unlimited, July
International Film Festival Rotterdam, Jan-Feb
Pleinbioscoop Rotterdam, Aug
Every sensible Rotterdammer stays at home eating warming erwtensoep (pea soup) in bone-chilling January, conserving their energy for the summer months. Hotel rates are at their lowest, as tourists and many businesspeople do the same.
It's still cold and dark, but the weather is starting to thaw and the festival season is slowly kicking off.
International Film Festival Rotterdam
Cinema screens across the city are taken over by this well-patronised film festival, in which independent and experimental feature films, documentaries and short films are screened. Starts in late January and runs for 12 days.
The sun starts to come out, and so do the locals. Cosy bruin cafés are popular meeting places for friends, tulips tentatively bloom in parks and gardens, and street stalls sell hot sugar-dusted oliebollen (deep-fried balls of dough).
Tulips and spring flowers make a colourful show in parks and gardens. The weather is pleasant and most hotels levy high-season rates.
Rotterdam Marathon (www.nnmarathonrotterdam.org) is held in early April and incorporates a kids run, beginners run and a quarter marathon as well as the main event.
Bohemian types converge on art, dance and performance events staged in unusual venues across town during this four-day festival.
Koningsdag (Kings Day)
King's Day celebrations occur on the 27th (26th if the 27th falls on a Sunday), with street markets around Coolsingel, Witte de Withstraat and Nieuwe Binnenweg.
Weather can be sunny one day, rainy the next.
Opbouwdag (Construction Day)
Commemorations are held on Opbouwdag (Construction Day) on 18 May, remembering the devastation wrought on the city by German and Allied bombers during WW2, but mainly celebrating the city's reconstruction. Events include tours of buildings.
Poetry International Festival
Celebrating quality poetry from the Netherlands and worldwide, this one-week festival in late May–early June offers talks, readings and other events.
The new herring season arrives to great acclaim, and Rotterdammers snap up their share of the 70 million-odd silvery fishes that are consumed in the Netherlands each year. They also take every opportunity to eat and drink outside, although the weather doesn't always facilitate this.
Rotterdam Architecture Month
Inaugurated in 2018, this event celebrates the thing that Rotterdam is best known for – its architecture. Conferences, building tours, guided walks, lectures and many other events are scheduled.
Rotterdam Bluegrass Festival
The vibrant, multicultural Noord neighbourhood is the location of this popular music festival.
Long sunny days are perfect for spending afternoons and evenings at a terrace bar or cafe, and for attending music festivals such as Metropolis and North Sea Jazz.
Attracting massive crowds, this free one-day event in Zuiderpark features up-and-coming bands from around the world.
North Sea Jazz Festival
A fabulously colourful street parade is the lynchpin of this celebration of the multicultural makeup of the city.
Many of the locals are holidaying by the sea, so the festival calendar is almost clear. Hotel rates lower; some restaurants close for annual holidays.
Duizel in Het Park
Vroesenpark turns duizel (dizzy) with events during this three-day festival, hosting an exhilarating mix of literary discussion, theatre, music and art.
Picnic-laden locals head to Museumpark on blissfully balmy summer evenings to attend the biggest outdoor cinema in Europe.
Autumn arrives, and the city's leafy parks are ablaze with colour. The weather is perfect for exploring by foot or bicycle. The mosselen (mussel) season starts, and plenty of these more-ish molluscs are enjoyed with frites.
Held in late September, this four-day festival includes an art and culture program, the Pridewalk and lots of parties.
Foodies swoon at the quality of the new-season white asparagus seen in markets and on menus. The weather is wet and cold; hotel rates start to fall.
Rotterdam Harbour Run
A 10km-long obstacle race through the Port of Rotterdam (www.harbourrun.nl).
The social calendars of locals are quiet after the summer flurry, and people start to look forward to Christmas celebrations. Sinterklaas (St Nicholas) arrives at Willemsplein by boat in the middle of the month, when the weather is getting cooler, and is greeted with squeals of delight by children.
Rotterdammers build up their energy supplies with steaming bowls of hutspot (hotchpotch; stew) and stamppot (mashed pot; stew of potato, vegetables and sometimes sausage). Christmas decorations prettify shopping strips, and the country's most spectacular New Year's Eve firework display occurs at the Erasmusbrug.