Over the years Kew has been one of the World Heritage Sites I have visited most regularly. Moving from a place I enjoyed for chasing ducks as a child, through to a pleasant garden and on to a site where it is clear to see its role in the development of scientific research. 

In 2003 Kew became London's 4th (and largest) World Heritage Site. It is set next to the river Thames upriver from central London. The grounds themselves are actually quite expansive and could easily fill a whole day if you wanted to really get into them. The plants are actually rather interesting (even if you are not a keen horticulturalist), and there was enough to see to satisfy me.

For me though the main point of interest was the architectural ensemble of the main greenhouses with the magnificent Palm House being my highlight. You will be hard pressed to find better examples of Iron and glass architecture than this, the detailing, especially on the spiral staircases, is magnificent.

The other glass houses house some great exhibits, carnivorous plants and the largest flower in the world being two examples and there is plenty here to keep you entertained. Then there are other small little things around, such as a Japanese Garden and a large Pagoda all set in well kept gardens.

In the last decade the opening of the wonderful tree top walk has added another interesting element, one that shouldn't be missed. It has helped focus on the arboreal collection as well.

Kew has also become great place for Londoners to visit in the Christmas period when the grounds are magnificently lit, though if you are interested you will need a separate night ticket to see them and these are popular so you may have to book in advance.

It is very simple to get there from Central London as it has a tube and mainline station nearby and its location on the river means it is also served by Thames ferry service. Additionally it is close to Heathrow Airport, so could be visited if you have a layover there.

(You can even, like me, use it as a start or end point of a run that takes in all four of London's WHS, if you have a handful of hours to spare and some shoes that will carry you over the 16 miles between here and Greenwich).

It is well worth a visit if you have some spare time and is the sort of place that makes living in and around London so exceptionally rewarding.