Waiting for the snow to melt

Supposedly there is no such thing as a stupid question, well here's my submission/attempt for the day.
 
Where/what is the mountain?  I grew up in Erie,... my family never had a boat, but I got out with the parents of friends quite a bit.  I was under the impression that is was a shallow ridge that runs roughly parallel to the Freeport area shoreline.  Depths go from ~60' to 45' as you go north then drop back off to 60's and deeper as you go north.  Recently someone said the Mountain is an inverted mountain with the peak being the ~220' depths found at that end of the lake.
 
In the mid 80's I remember a ship going down around the mountain.  It was rumored to have gold on board. I witnessed this area being guarded by patrol boats as (from what I was told at the time) divers tried to recover the gold and/or ship.  I was certain this was the mountain, because is was a very quick trip from Freeport and not too far out into the lake, but a recent conversion has me questioning myself.
 
Any input is appreciated.
Thanks
CJ 

Thanks for the map.  That is what I have always been told and understood to be the mountain.  Sometimes the strength of other opinions makes you question your beliefs.  I was looking for reassurance.