Technically, "sea level" would be zero feet. Sea level is defined as being level with the sea's surface.
So let's say men build a sand dune 3 feet high along a beach with the beach being level with the ocean (at zero). That dune would be 3 feet above sea level. Let's say wind piles another 2 feet of sand onto the dunes-- the top would be 5 feet above sea level. Let's say you drive 40 miles inland and you encounter a hill that slopes upward 20 feet before it crests. At the top, you are 20 feet above sea level.
The important thing to remember about sea level is it is always about something else in geography. It's about an elevation of land, hill, or mountain. It can be about a river set far inland-- the sea level is based on the elevation of land at the level of the river but as 'sea level'. So the land on which the river sits might be 500 feet above sea level, with higher land surrounding the river.
It is NOT about how high the sea level is because sea level is always the surface level. But geographical features can be above--or below--sea level. As another answer states, New Orleans is below sea level in that area. But the mountains in the State of Georgia are higher than sea level-- as is the land between New Orleans and the mountains in Georgia.
Victoria is located at an elevation of about 66 feet above sea level.
Washington, Iowa is approximately around 663 feet above sea level.
Bury, a town in England, has an elevation ranging from 223-328 feet above sea level.
Gresham, Oregon is approximately 200 feet above sea level.
Naples, Florida is approximately 3 feet above sea level.
It is 781 feet above sea level.
Baltimore is 33 feet above sea level.
It is 2.389 feet above sea level.
617 feet above sea level.
It is 295 feet above sea level.
Toronto is 380 feet above sea level.
80 feet above sea level )
It is 863 feet above sea level.
594 feet above sea level.
Baltimore is 33 feet above sea level
Chantilly, Virginia is 322 feet above sea level
About 7,000 and 8,000 feet above sea level.