This is rather news to me - I think of people protesting the enclosure of commons as doing this a) a lot earlier and in more rural parts: Today in London’s parklife: 1000s destroy enclosure fences, Hackney Downs, 1875:

The 1870s were a high point of anti-enclosure struggles in the London area, following on from a decade of (mostly, though not exclusively) peaceful campaigns to prevent large open spaces being developed in the 1860s. Wanstead Flats in 1871, Chiselhurst Common in 1876, Eelbrook Common (Fulham) in 1878, all saw direct action against fences, as part of long-running resistance against the theft of common land.
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Many of these struggles were characterised by the large-scale involvement of radical movements, as London radicals, secularists and elements who would later help to form socialist groups made open space and working class access to it a major part of their political focus. Radical land agitation, notably through the Land and Labour League, was beginning to revive the question of access to land as a social question, and within cities this manifested as both battles to defend green space, and propaganda around the theft of the land from the labouring classes.

Centuries of hard fought battles saved many beloved places from disappearing, and laws currently protect parks, greens and commons. But times change… Pressures change. Space in London is profitable like never before. For housing mainly, but also there are sharks ever-present looking to exploit space for ‘leisure’. And with the current onslaught on public spending in the name of balancing the books (ie cutting as much as possible in the interests of the wealthy), public money spent on public space is severely threatened.
Many are the pressures on open green spaces – the costs of upkeep, cleaning, maintenance,
improvement, looking after facilities… Local councils, who mainly look after open space, are struggling. Some local authorities are proposing to make cuts of 50 or 60 % to budgets for parks. As a result, there are the beginnings of changes, developments that look few and far between now, but could be the thin end of the wedge.
So you have councils looking to renting green space to businesses, charities, selling off bits, shutting off parks or parts of them for festivals and corporate events six times a year… Large parts of Hyde Park and Finsbury Park are regularly fenced off for paying festivals already; this could increase. Small developments now, but maybe signs of things to come. Now is the time to be on guard, if we want to preserve our free access to the green places that matter to us.

HEIR, the Historic Environment Image Resource:

HEIR’s mission is to rescue neglected and endangered photographic archives, unlock their research potential, and make them available to the public.
HEIR contains digitised historic photographic images from all over the world dating from the late nineteenth century onwards. HEIR’s core images come from lantern slide and glass plate negatives held in college, library, museum and departmental collections within the University of Oxford. New resources are being added all the time, including collections from outside the University.

Dragon’s teeth and elf garden among 2025 additions to English heritage list:

The heritage body publishes a roundup of unusual listings to draw attention to the diversity of places that join the national heritage list for England each year.
As well as the anti-tank defences, this year’s list of 19 places includes a revolutionary 1960s concrete university block, a model boat club boathouse built in 1933 by men who were long-term unemployed, and a magical suburban “elf garden”.

Art history is too important to be the preserve of the privileged:

The act of looking has become commodified as technology companies ‘mine and sell our attention like coal’, as Kee writes. Letting art history become endangered and drift further into elite status is not only unfair, it’s also perilous. ‘Art history gives you tools to interpret the visual world and makes you more of a critical viewer of political messages, advertising and a barrage of social media images,’ says Perry. ‘It’s dangerous if you can’t examine these things critically.’