Opened in 1858, St. Mary's nestles next to the western end of Kensal Green Cemetery. It's worth a visit for the exceptional and varied collection of mausolea, which cluster round the chapel at the northern end of the cemetery. There's a large memorial with inscriptions in Dutch and French commemorating the Belgian soldiers who died in the Great War, and a number of other tombs worth visiting.
Sadly, maintenance in this cemetery is not all it could be; several tombs have been vandalised and others seems to be just falling apart, the ground off the main paths is uneven and potholed, and one of the more lovely mausolea has lost its door and windows and is being used as a wood store. Further south, ground has been reclaimed for new burials by piling up earth over old ones; the view towards the canal is all black granite and coloured windmills.
Visiting: Very busy on a Sunday lunchtime, with cars zooming through the older part to the newer. Check opening times because gates close early (5pm in summer, possibly earlier in winter). Kensal Green station is within walking distance, and several bus routes serve the area.