So, if I have
window.location.hash = '';
both will return the URL without the hash or anything after it.
With regards to your edit:
Any change to
window.location will trigger a page refresh. You can change
window.location.hash without triggering the refresh (though the window will jump if your hash matches an id on the page), but you can't get rid of the hash sign. Take your pick for which is worse...
MOST UP-TO-DATE ANSWER
The right answer on how to do it without sacrificing (either full reload or leaving the hash sign there) is down here. Leaving this answer here though with respect to being the original one in 2009 whereas the correct one which leverages new browser APIs was given 1.5 years later.
With respect to this answer that was given