Nice dive site. I've been here 4-5 times and really enjoy it. There's usually a fair amount of wildlife in the summer. There is no parking for people who aren't Nahant residents during the summer months, so it's best to go during the off season. Just stop by the police station and they will usually let you go with no trouble. Head to the left like you're going to cross over to 40 steps (a dive which is great fun to do if you have decent air consumption) and you will get into a bunch of rocks with crevices and cracks that are nice to explore.