The Victorian public park movement was just beginning to flower in 1830, and Bath wanted in. Private subscribers funded the new grounds, intending them as a polite refuge for the genteel city above. Victoria's role was symbolic, but the symbol stuck. She returned at age eighteen, the year of her coronation in 1837, to find a tapering triangular obelisk waiting for her near the east entrance. G. P. Manners, the city architect, had designed it as a coming-of-age tribute. Three stone lions couchant guard its base; a low relief of the young princess is carved into the plinth. The whole monument was unveiled on coronation day itself, 28 June 1838. For nearly a century the park stayed in private hands, run as part of that distinctly Victorian experiment in respectable public leisure. Bath Corporation took it over only in 1921.

In the north-west corner of the park, the Botanical Gardens opened in 1887, and they have since gathered one of the finest collections of limestone-loving plants in the West Country. Walk among them long enough and you arrive at something unexpected: a small replica of a Roman temple, sitting calmly under English skies. It was originally built for the British Empire Exhibition at Wembley in 1924, the same blockbuster spectacle that gave London its first Wembley Stadium. When the exhibition ended in 1926, the temple was dismantled, freighted to Bath, and reassembled in the gardens, where it has stood ever since, eventually extended into a modest interpretation centre. Above it, the Great Dell drops away into the trees, a former stone quarry that 1840s gardeners planted with North American conifers tall enough now to swallow conversation. Sound goes quiet there. The temperature drops a degree or two.

Visit the Queen's Gate entrance and you meet two bronze-coloured Medici lions on plinths, each with a gilded ball under its front paw. They look untroubled, but they have a story. The original wrought-iron gates and railings that ringed the park were torn out during the Second World War as part of Britain's national scrap-metal campaign, melted down for the war effort along with countless garden fences and church railings across the country. The lions themselves stayed, but their iron armatures rusted inside. In 2007, with Heritage Lottery Fund support, Bath and North East Somerset Council ran a programme of repair: new armatures, fresh bronze patina, restored gates with gilded decoration, and over a mile of reinstated perimeter railings. The bandstand was rebuilt. The Royal Crescent's ha-ha was tidied. Even the cast-iron lanterns that once flanked the gates were replicated and re-hung.

Forty-nine acres of park can absorb a lot of life. The lawns hold a bowling green, a putting green, twelve- and eighteen-hole golf courses, tennis courts, a skateboard ramp, and a children's play area that families spread out across all summer. Hot-air balloons inflate over the grass during the Vintage FunFair, sending their burners hissing into the morning. In winter an ice rink appears; in spring the Bath Children's Festival fills the May bank holiday with noise and bunting. The Tour of Britain has rolled through. Movie nights flicker across open ground. The park holds a Green Flag award and a Grade I listing on the National Register of Historic Parks and Gardens, but the honours feel almost beside the point. What matters is that a city of golden stone has, in its middle, a great breathable lung where everyone, from the toddler with a kite to the pensioner with a putter, walks free.