Checking out a project's first commit with git

Is there an easy way to find the SHA1 of the first commit in a project with a long history wit开发者_JAVA百科h git?

Just off the top of my HEAD, this should get one of the 'first' commits of the current branch.

git rev-list --reverse HEAD | head -1

(If the branch contiains two unrelated branches which have been merged together, it's not guaranteed which root you will get but you could use --date-order to select the oldest.)

git log --reverse | head -n1