The heath has much to offer. It is hard to believe you are still in the middle of London when you're walking here. There is peace and tranquillity if you want. There are bracing walks that will give you great exercise. There are the picturesque ponds and the separate men's and ladies' lakes for swimming. There are people walking dogs, playing frisbee or kicking a football or, you can go jogging in this lovely environment. Kenwood House is beautiful and they do great afternoon teas and refreshments (though not cheap).
It sometimes gets quite busy during popular holidays or when the weather is exceptionally good but the mood is so nice at these times, it doesn't matter.
This place is a gem. I go several times a year and I always enjoy it what ever the weather.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.