I just finished doing what you describe. I took a small sledge to the marble saddle, which broke apart easily and exposed the leading edge of the tile and mud. I then used a combination of a cold chisel...the one with the red hand protection that they sell at Home Cheapo worked nicely...along with a medium sized pry bar and a couple of crow bars.

I went at it from the doorway first and banged away at an angle to reduce vibration. Crow bars are nice, but my space was confined (~5'X 9') so maneuvering them around was tricky.

I was actually more concerned smashing up the cast iron tub (from a vibration standpoint) than I was going at the floor. Wrestling that "chicken wire" underlayment is a real blast let me tell you! Leather gloves and long sleaves are a must along with eye protection.

Good advice from spanky67 -- start at an edge, use a cold chisel and prybar. A 5 lb. hand sledge can be handy occasionally. I had a similar tile shower surround to remove (right down to the pink color, though it'd been recoated with something or 'nother that was white). Also have some good wire cutters on hand. As you're breaking it up, the wire will tend to hold the pieces together. Being able to cut it will let you remove smaller chunks and get them out of your way.

You can rent a small wet concrete cutting saw that is virtually dust free, but it uses water, so you have that as a concern. The advantage is that you can make a series of relief cuts perpindicular to one another a couple of inches apart. Then you can run some cuts diagonally as well. You could do this on a half day rental, as that is usually a minimum with rental yards. After returning the saw, come back and have fun chiseling away. Makes the chore of chiseling a lot easier with less effort.

Whatever route you take, safety up espscially with eye protection when chipping concrete.

If you have a hammer drill with a chisel bit, that might help you with the chiseling part of the show. They are not as aggressive as a rotrary hammer and will not cause a whole lot of vibration.

Unless the mud bed is damaged (serious cracking) there is no reason to remove it.
Smooth off the top after removing the old tile and lay new tile on the bed.
Full mud beds are not as common as they used to be since it is a lot more expensive.

This is GREAT information. Many thanks to all. I will post a follow-up on Monday with an update. Looks like I have a fun weekend ahead of me :-)

We did this last year. All you need is a wire cutters, small hand sledge and a crowbar. Tap the concrete, you don't have to slam it, 4 to 10 times and it will break, lift up a corner slightly, 1/2", and tap some more and everything will break. The less you pound the less dust you have. Also larger pieces are quicker to remove than a million marble sized pieces.

"Tap the concrete, you don't have to slam it, 4 to 10 times and it will break, lift up a corner slightly, 1/2", and tap some more and everything will break."

This really depends on the age of the mud bed.
In a 105 year old house it could be anything frm new cement board (easy) to a full thickness mud bed job that is 2-6 inches thick with plumbing and joists embedded..

For those that are following this thread I thought I would post an update:
I rented a rotary hammer (Hilti TE-16) from Home Depot and using an assortment of bits was able to clear a 10x6 area of 2" concrete+tile in less than 5 hours. Also used a heavy hammer, crow bar and wire cutters.

Vibration/noise was not that much more than you'd expect from a heavy duty hammer drill. There was some dust but not as bad as demolishing plaster. The hardest part of the job was carrying the pieces of concrete and buckets of rubble and tile down to the dumpster...

Many thanks for the tips and advice provided above.

brickeye; The OP said 2" in his original post.

I want to know if I can just go over the tile/concrete. On the shower stall we are making it bigger. Can I leave the current base as an anchor and build over it?

I just went through a complete demo of my old 35yr old custom shower base. thanks for all who posted here. That helped me get started. Spanky67 was right. You go at it an inch at a time with a chisel. However, if you can rent a rotary hammer, that would save you a ton of time and effort. I first tried a hand chisel and a sledge hammer but could see that I would be wasting at least 4-6hrs on a 3'x4' shower base. Instead, I picked up a 3-in-1 rotary hammer at Harbor Freight for $80. It has a chisel/hammer function. It took less than 30 minutes to get all the concrete out. The trick is to place the chisel right between the tiles. Mine were the small size ~1x2" or so. Going right on the ceramic tile is much harder to break.
The hardest part once done was actually hawling the heavy concrete downstairs.

If any of you are remodeling a custom shower base with a lead/metal shower pan liner, here's a tip on how to remove the liner and the drain: Don't wast your time trying to unscrew the old drain out to get to the pan liner. You'll waste so much time because the drain is metal and it's so rusted that you can't unscrew it.
What I did in my case was first get a pair of snips and cut the pan liner all the way to the drain, then cut around the drain to free up the liner. Once it's removed, discard it. By then you would have exposed your subfloor. Then use a reciprocating saw or circular saw and set it to 1/2" or 5/8" deep(depending on your subfloor thickness), then cut a 2'x2' section. remove it and pry it out. once you can see the drain pipe and have access to it, you can take a hacksaw and cut below the drain. Discard the drain. You can easily replace extend/raise the pipe up iff needed by adding a small section to it.
Caution: Always be careful when cutting into the subfloor. even though the subfloor below showers/bathrooms usually is more roomy (at least 8 to 12" deep), you can still run into pipes that you could accidentally damage. That could cause you more work/headache than you ever need.

That's it!
I wish I read this post before starting my remodel. it would have saved me some time.

Happy Remodeling!
MaxRelax