A trio of free events over the next couple of days, from our calendar.

Extreme animals
Grant Museum of Zoology, 24 November, 10–4, Free
UCL’s small but perfectly formed zoology museum presents a family-friendly event this weekend. They invite you to ‘meet some of the biggest, smallest, heaviest, lightest, cutest, ugliest, oldest, newest, weirdest and wildest animals’, while putting on educational activities for kids.

Blood, guts, children and power
Meet Holborn Tube Station, 24, 25 November, 11–1, Free
Take a tour of London’s medical quarter courtesy of the Wellcome Collection. The guided walk takes in Holborn, Bloomsbury and St Pancras, visiting historical sites such as the Royal College of Surgeons and Coram’s Fields. Note that pre-booking is advised.

Going underground
Natural History Museum, 25 November, 12.30 and 2.30, Free
There aren’t any real caves in South Kensington, unless you count the Tube station. Nevertheless, you can learn all about their formation and exploration at these afternoon talks from museum curators.