Guppy isn't a bad place factoring in the price ($20 the last time I was there) and the distance (about 1 hour from my home). Crowds vary. Sometimes there were only 2 or 3 other divers; sometimes there were 20.
Visibility depends on who's there and how many. I've seen some good vis, but that can get messed up easily.
Entry is walk-in shore or from the shore you can walk out on floating piers for your favorite deeper entries. That part of the quarry is fairly shallow (15 to 20 feet). As you stand at the entry, it gets shallower to the left (up to just a few feet and can ge quite warm) and deeper to the right.
In that general area there are remnants of a Cessna 152 or 172 cabin (no wings, tail, etc) a few small boats, and I think a truck cab.
Heading farther to the right from the shore (following the lines) you'll find a sailboat suspended in the water column. The first time I was there after this boat was added, I didn't know it was there. As I was going past (under) it, it got dark from the shadow. I thought it was odd. Never saw it on the return leg, either. It wasn't until I mentioned the dark ominous feeling to the fellow working there that I learned about the boat.
The lines lead to 2 more boats in the water. I forget the name of the closer one, but the one farther out is called the Damned Fool. My buddies and I joke about it saying you are a damned fool if you go there - because this is one cold quarry.
At one point near the closer of those two boats you'll find a junction of lines that head to the left. If you follow it, you'll be heading to some other attractions. It can seem like a long journey, but eventually you'll come across another boat (sailboat, I think) that is suspended in the water column, but this one is oriented up and down. I don't recall if it is bow or stern up, but it's a little trippy to see it the first time. Beyond that is what I think is the last attraction in that direction - a small bus like the kind churches commonly have (4 or 5 rows of seats). You can easily enter and go through it.
Most of these are 50 feet or less if I recall. That last few times I was there (once last summer and once or twice the summer before that) I stayed mainly in the shallow area no deeper than 30 feet. It was just to go blow some bubbles.
The amenities include his and hers communal changing rooms, a port-a-pot, and an on-site compressor for cylinder refills, but I never got my fills there. There are a number of picnic tables. No shop or snack shack.
I much prefer Bainbridge due to all of its amenities, but several years ago they priced the fee far above what I am willing to pay for any brown-everything quarry (currently $35 if the web site is up-to-date).
I just searched and found a map at
http://www.icarusphotography.com/Lazydiver/UW Map_Guppy quarry map_Nov2010_ACP.jpg. It looks like they added a few things since I last checked. The entry is from the left side of the diagonal spur on the map.
There also seems to be an official web site at
Tales from Guppy Gulch — Delta, PA
John
