Panama Canal Question, please ty?

What are the physical characteristics that made the panama canal a poor choice for a canal site

If it was a poor choice, why were they successful building it and why are they expanding it? I dont understand your question...If you want to know what were the backwalls that they found during the construction, I would ahve to say that medicine was not quite developed at the time and many workers died of malaria...but that was about It...

Let's do this a different way... suppose YOU tell ME where else they could have built the canal... where would a better choice have been.?

The Panama Canal was built on the thinest point between the Atlantic ocean and the Pacific ocean. Obviously the better choice would be to dig at the widest point in northern Canada where the continent is more solid and would have kept workers employed for much longer which would have greatly improved the Canadian economy, brought more immigrant workers and boosted that countries ethnic diversity. Of course, the Canal might not be finished yet...