The Retiro was a royal private garden for two hundred years before Madrid was let in, and that is why its trees are old.
Philip IV's court laid it out in the 1630s as the grounds of a palace that has since vanished, leaving the planting behind; the park only became public in 1868. Nine of the trees we map stand inside it, and they are spread wide enough that finding them is a proper afternoon rather than a lap of the pond. The oldest is a Montezuma cypress near the Paseo de Mexico, a species from central Mexico that arrived in Spain with the empire and outlived it.
All 9 stand in Madrid, which maps 17 remarkable trees in total.
Montezuma Cypress (Taxodium mucronatum). This tree carries two stories about its own birth that cannot both be true.
Mediterranean Cypress (Cupressus sempervirens). This cypress has stood on the Plano de la Flor terrace since before the Royal Botanic Garden moved to its current site.
Caucasian Elm (Zelkova carpinifolia). Measured against every other tree in the Royal Botanic Garden, this one wins on height, reaching by some counts over 30 metres in the garden's north zone along the Paseo de Mutis, tall enough that garden staff and visiting botanists disagree on the exact figure by several metres depending on measurement method.
European Yew (Taxus baccata). Rather than one trunk, this yew splits into three, each thick enough to measure separately: 142, 120 and 140 centimetres around, fused into a single crown 18 metres wide standing beside the eastern wall of the Palacio de Velazquez, a red-brick exhibition hall built in 1883.
Himalayan Cedar (Cedrus deodara). This cedar stands directly in front of the pond at the Palacio de Cristal, a 19th century glass and iron pavilion built in 1887 to exhibit plants and animals brought back from the Philippines, and it has spent most of the pavilion's history as part of the same postcard view: the glass palace reflected in the water, framed by the cedar's dark, tiered branches.
Silver Maple (Acer saccharinum). This maple gave up on having one trunk early.
Cedar of Lebanon (Cedrus libani). At 33 metres this is the tallest tree on the Retiro's catalogued list, and it does not look it, because it stands at a junction of wide avenues where nothing nearby gives the eye anything to measure against.
Tasmanian Blue Gum (Eucalyptus globulus). In February 2015 the Comunidad de Madrid revised its register of singular trees and published two lists side by side.
Bald Cypress (Taxodium distichum). Several bald cypresses grow directly out of the pond in front of the Palacio de Cristal, their trunks and lower roots permanently submerged, a planting scheme that only works because this particular conifer, unlike almost every other cone-bearing tree, tolerates and even prefers standing water.
More parks worth the walk: every park we map. Or explore by city: Guimaraes · Fukuoka · Amsterdam · Lisbon · London · Paris