I would definitely recommend a visit to Pere Lachaise to anyone visiting Paris. Many famous authors and artists are buried here. We went specifically for Jim Morrison but were surprised to find many more big names. There is obviously barricades around some of the graves, but many people still bring flowers and items to place there. Jim Morrison's grave had many bouquets, pictures, etc. It is a big place though so definitely grab a map on your way in. Also, try to go earlier in the day - we got kicked out because it was closing and we weren't able to see all that we wanted to.