The city register counts fourteen.
Canary Island Date Palm
Every Canary Island date palm on the French Riviera arguably descends from one garden on Nice's eastern port, where Baron Vigier is said to have acclimatised the species in France for the first time in 1864. This page maps every canary island date palm on the site, 6 so far across 5 cities.
That rests on the garden's own preservation society rather than on any independent record, so take it as the claim it is. The species is easy to admire and impossible to date, because a palm lays down no growth rings to count. Valencia's Palacio de Pineda has a construction date to the year, 1728 to 1731, and its palm has nothing at all; you can order a coffee under it. Barcelona's double row along the Vil.la Amelia avenue produces its own small disagreement, since the city register counts fourteen palms and the garden's chronicler counts fifteen. Valencia's other three stand in a row so recognisable that a bar took their nickname.
Barcelona
Valencia
You can order a coffee under this one.
Three palms standing together at the entrance to a single street have become a landmark specific enough to have lent their nickname to nearby shops and a bar.
Cork
A palm tree growing outdoors on an island in Cork Harbour, at the same latitude as Newfoundland, is the clearest single demonstration of what the Gulf Stream does for this stretch of Irish coast.
Nice

Photo: CHRIS230 (CC BY-SA 2.0)
Every Phoenix canariensis lining a promenade or a hotel driveway anywhere in France arguably traces back to one estate on Nice's eastern port.
Bilbao
More than forty species of tree grow inside the walls of a Bilbao almshouse.
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