Lit up like a tropical Christmas tree in December, with coils of blue fairy lights spiralling up tree-trunks and illuminating foliage, Trianon Park (officially, Parque Tenente Siqueira Campos) never looked lovelier. Of all the city’s parks, for downtown shade and lavish greenery, this one takes the biscuit: it’s dense and lush, deliciously shady, well endowed with benches (take a memo, Ibirapuera) – and no matter how often you wind your way along its curly paths, it’s the same surprise each time to find this scrap of Atlantic forest set here, in the midst of Avenida Paulista’s business-like hurly burly.

Daytimes in the park are about strolling and sitting: too small for serious joggers, Trianon is better for people on slow time, and so it draws lovers and pensioners, small children and lunchtime office workers into its shade. At night when the park is closed, a drive around the block along Alameda Jaú reveals athletic young men by the park fence, stepping hopefully out of the shadows in search of passing trade, and lifting their T-shirts to reveal muscular chests.

As compact as a park has any right to be, Trianon stays just the right side of too small, spilling down over Alameda Santos to nicely double its size. The curved footbridge that carries you over is mirrored deep underground by the Nove de Julho tunnel, which pierces the ridge crowned by Avenida Paulista, passes under part of Trianon and then speeds on downtown.

Named for the club that once faced it across Paulista, where the MASP now crouches, Trianon has had its good times and its bad times, from its inauguration a year after the Avenida itself, in 1892, to its fashionable 1920s and the wilderness years that followed, until Burle Marx himself had a hand in its rehabilitation in 1968.

Try to resist looking in for a breath of forest air as you pass, going about your oh-so-important Avenida Paulista business, with Robert Frost’s siren words spooling through your mind:

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