I was at St Louis Cemetary in January. I believe it was Lafayette, as the individual above stated.

Sorry for the delay, it was pointed out on a tour, available at a reasonable price.

At the time we went (Oct 2017), you could go into the cemetery without a guide after paying an admission fee. The more recent answers indicate that policy has changed. Too bad, but when unsupervised people take advantage of a historic site and active cemetery to vandalize graves, that's the consequence. We booked a carriage tour of historic New Orleans that had the option of visiting the St Louis No 1 as well, without paying an extra fee. That worked out great, and our carriage driver was extremely well versed in the cemetery. Because of our interest and questions, he spent more time with us in the cemetery than was usual. We gave him a generous tip. I do recommend visiting the cemetery with a good guide. It will make for a rich and rewarding visit, and surprise you with what you will learn.

There are several different companies that offers tours here. You would need to check with the tour operator that you were considering. There are some areas of the cemetery that are narrow and some places are uneven. However, I imagine the more experienced companies have been asked this before and they would know the best route through. You need to make reservations in advance (access is only granted as part of a tour due to vandalism), so ask this question before you book.

A good tour guild can make it 30 or 45 minutes. very interesting.

About one hour

Lots of options for touring this cemetery. However, unless it's part of a combo tour your already taking, if you just wanna check it out. Follow what mrmeman1 advised you can go into the large depot station next door to it & pay for tix at the desk & a tour guide has a designated time to meet you at the same depot where you will walk across the street to tour it. Just an fyi, the night tour is not of this cemetery but of another one. Lafayette cemetery on the other side of town is the free one that has been in some movies I'm sure you have seen also. You won't be disappointed it's informative & a little creepy. My & my husband's cameras went a little haywire during our tour.

Three chicks hands down. The 9 AM tour was great because it wasn't too hot yet.

Earlier in the morning the better, does get hot. We went through Witch Brew Tours, Rose the guide was great! Found a groupon which made it a two for one. I enjoyed it and would do it again.