Horniman Animal Walk

The Animal Walk at Horniman Museum is free, which immediately makes it worth squeezing into a London itinerary. It's not a full zoo - more a collection of enclosures spread across the museum's grounds in Forest Hill, where you can see everything from llamas to emus without paying a penny. The animals are genuinely well-kept and the space feels less cramped than many paid attractions around the capital.

You're looking at around two hours maximum, depending on how long you linger. Kids will sprint through it in forty minutes flat. The real draw here is combining it with the museum itself - Victorian taxidermy, musical instruments, natural history stuff - so you're getting actual content for your visit rather than just animal spotting. Families visiting Lovat Parks (about five miles away in Chislehurst) should absolutely factor this in as a day trip; it's straightforward to reach on the Overground from most of South London.

Timing-wise, weekday mornings are far less rammed than weekends. Bring a snack because the on-site café is fine but nothing special. The grounds are pleasant for a wander even if animal enclosures aren't your thing - there's decent views over South London and the museum building itself is genuinely interesting. It's not a replacement for Whipsnade Zoo, but as a free add-on while you're exploring London? Absolutely worth it.