How to make a cave

I have gotten myself some terracotta pots that I want to use as hiding places for some of my fish. I would like to put the pot upside down and have an 'entrance' on the side. How can I make a hole without smashing the whole pot? Is there somebody that has done this before?

I'd think that the best way would be to use a drill.
I found this that might be of use for you!
http://www.examiner.com/article/how-to-drill-drainage-holes-for-container-gardening

I used to make caves out of 4 inch terra cotta saucers silicones together and cover them with gravel to create a small cave for my bristlenose plecos. I would made a small rounded opening in the edge of one by breaking away a small amount of clay from the edge bit by bit with a pair of needled nose pliers and then using a dremel to sand the edge of the break to create a rounded opening. Will have to look to see if I still have a picture of one to show you what I mean.

As for creating a hole in the side of a pot, this could be more challenging as the clay does have a tendency to crack (I've broken more than one saucer by being over eager to get the job done and tried chipping away too much clay at a time.)

I'd experiment with an old pot first to see how easy it is to drill the hole. Once you have a hole big enough you can then sand the edges to make it larger without worrying about cracking the pot.

I heard it works best to soak the pots BEFORE you do any drilling... less likely to crack that way, HOWEVER, disclaimer... I've never tried it!!!

@nyleveiam wrote:I heard it works best to soak the pots BEFORE you do any drilling... less likely to crack that way, HOWEVER, disclaimer... I've never tried it!!!

Yes, it works.
And you might wanna use diamond blade on grinder or hole saw:
http://www.homedepot.ca/product/1-3-8-in-tile-hole-saw/991033

What fish are you aiming for? If they are a small species, coconut caves are much nicer to deal with and to look at.

I agree about the coconut caves! Plus, moss will easily grow on them!!! BONUS!

I know, but I don't know where to get those; I am no longer in the tropics! Plus the wood from the coconut is very hard so making a hole in it, is not that easy either.

This is true, best way is with saws/drills. If you decide to try, I do see coconuts at my Superstore semi-regularly so you may be able to find them at your local grocery store.

I buy a coconut and poke a hole in it. Drain, then wait a day. Saw it in half, take out the inconvenient white stuff, cut 2 doors and voila, 2 caves for $2.
I cut them with a hacksaw.

I think I will wait until I go back to Mexico. I am sure I can find somebody to cut this coconut for me the way I want it.... I do not have a hacksaw here and in Mexico they cut it with one bang in half using a machete.

i have a hole saw and a hack saw.. I might do this. >.> my wife will enjoy the milk..