Q:

Chamishim Umatayim - mi yodeya?

Who knows two hundred fifty?
Please cite/link your sources, if possible. At some point at least twenty-four hours from now, I will:

Upvote all interesting and relevant answers.

Accept the what I think is the "best" answer.

Go on to the next number.

This one should require a little less digging, I think.

A:

According to R' Akiva, cited in the haggada, there were 250 plagues (or "plague components") during קריאת ים סוף. 
Korach's "עדה" consisted of 250 men. (Bamidbar 16:2)

A:

There were 210+40=250 years from entering Egypt to entering Israel (or, to the tune, "two FIFty were the YEARS outside IS-RAEL").

A:

250 [shekel, I think] was the quantity of k'ne vosem in the shemen hamishcha (anointing oil). (Sh'mos 30:23.)

