The Gooseneck is the lower half of the whole round, consisting of eye of round, heel of round, and bottom round:

Parts of the round steak, bone in:

A whole gooseneck:

It's parts:



Whole Eye of Round:

Beef whole bottom round;

Beef Whole Bottom Round (w/rump sectioned off):

Grain runs diagonal on the piece, so slice across the grain.

These are the parts of the gooseneck and how they are sectioned out.  Bottom Round can be tender when cooked medium rare, max, and sliced thin across the grain.  Rump is the tenderest, End cut is the toughest.  The heel is seamed out for cubes and stew; the center muscle looking like a rope is seamed out for longboil stew, like a soupbone - stringy and tough.