Baseball records guaranteed never to be broken. Mine is:

[Va Lefty]

8. Back to back no hitters by Johnny Vander Meer

"Johnny Vander Meer of the Cincinnati Reds pitched two consecutive no-hitters. In order to break this record, a pitcher would have to pitch three consecutive no-hitters — simply impossible!

1938 was Vander Meer's first full season; however, the often wild throwing lefty did not let that get to him. On June 11th at Crosley Field in Cincinnati, Vander Meer walked three while striking out four and allowing no hits against the Boston Bees. No Boston player even made it past first base. Four days later in Brooklyn, he was a little less steady. He walked eight and struck out seven in the very first night game at Ebbets Field. He needed a little help from some spectacular plays by his teammates and almost ended the streak himself when he walked the bases full in the ninth, but a well placed pop up by Leo Durocher ended the threat
"
.http://www.baseball-almanac.com/feats/featsjv.shtml