Whilst in Liverpool we visited Liverpool Cathedral, which is the largest cathedral in the UK. We didn't find that it was very impressive, considering it was completed in 1978, and many other cathedrals and castles were built hundreds of years ago without the technologies made available in the last century.
What was impressive though, was St James' gardens below the cathedral. This was the main city cemetery, used until 1936 and had over 57000 burials. Now they've moved quite a few gravestones from the centre to make way for a public park. The basin (before it was used as a cemetery it was the a sandstone quarry) is surrounded by gravestones, with areas at either end filled with quite a few. It was a really interesting place to walk around and learn about.