On our attempts to tour Honduras went to Taulabe Caves. Taulabe Caves was a perfect family day trip this past weekend. It was about an hour's drive from Comayagua for us to get to, but well worth it. It was $4 per adult and $0.50 per child, our 4 year old was free. This price included a private tour guide. For $4 more you can take the extreme tour and crawl through other areas.
If you look closely at this picture you can see the formation near the back that they call "the fountain".
Here is a youtube video I found that shows you a lot about the area we were in.