How do I completely remove and re-create a Subversion repository?

When I first created an SVN repository at ~/repo/myrepo, I had some files in there that I no longer want to be part of the repository. Instead of "removing" them (svn delete) so that they don't show up anymore in the current revision and future revisions, I don't want any trace of the files to be accessible at all, even by looking at old revisions of the repository.

I'm trying to completely remove the repository and start over, so I did this:

rm -rf ~/repo/myrepo
find ~/webapps/mycode -name ".svn" -exec rm -rf {} \;
svnadmin create ~/repo/myrepo
svn import ~/webapps/mycode ~/repo/myrepo -m "Initial import."

...but the repository still exists in its original form, including all of the revisions (it was up to rev. 70). Shouldn't this new repository be at revision 0?

It's accessible both through my "svn" website and my Trac website, and all of the revisions still show up. Shouldn't that first rm command have obliterated the repository? Why are SVN and Trac still displaying the original repository as if nothing happened?