Lockhart Style Pit

I'm assuming you're talking about the brick pits with fire on the floor? They go up into chimneys. You can see the soot in this picture of Smitty's

http://www.tmbbq.com/wp-content/uploads/2013/10/Lines-Smittys.jpg

http://www.bbq-brethren.com/forum/showthread.php?t=139025

When I was a child all bbq in GA was cooked over an open flame either in a brick pit or rarely one in the ground. Most did not have a chimney but were open on three sides and coals from a separate fire would be added as needed. Cooking rate of food was adjusted by moving food to cooler or hotter areas over the fire. Nearly all cooking was of pork, either butts, ribs, or whole hogs, some folks would cook chicken halves as well. Nearly all food was cooked using oak, hickory, or a combination thereof.

http://gizmodo.com/5987009/the-easy-cheap-way-to-build-a-kick-ass-bbq-pit-in-your-backyard

They're fairly simple... The draw from the chimney is powerful enough to bring the heat and smoke into the chamber. Louie Mueller has the brick pits but I think he moved his fire to where it's covered.

People complain about the cost of "real" BBQ. Just look at the size of that fire and the cords and cords of wood stacked out back. Real deal BBQ cost big $$$

Those are amazing pits Steve and I've only ever seen pics of them!

I want to make a pilgrimage down there some day and eat the food off of those pits!

If you really had a notion to build one of those pots you could actually blow up pics and count bricks then scale it down to a backyard size.

I've been to Kreuz quite a few times. The pits are different than the big tall one at Mueller's I saw. At Kreuz, they are long brick rectangles. They're about three to four feet tall at most and about the same deep. They have large rectangular pieces of plate metal that are the doors/lids (maybe four to six feet long) and they are counterweighted by a cable run thru a pulley which is attached to the counter weight. The fire boxes are surprisingly small open ended rectangles (maybe two feet by three feet by three feet). The exhaust is just a large brick chimney.

To my knowledge these pits must be grandfathered in to be legal in the state of TX for businesses. House Park BBQ in Austin has the oldest pits in Austin city limits. If you google them you'll see similarly styled pits on a smaller scale. Pretty cool stuff.