Maryland's strangely shaped 3rd Congressional district stretches all the way from Baltimore to Montgomery, and contains portions of both cities along with some rural areas in between. It weaves through skinny ribbons of four different counties. Some portions of the district don't even touch the rest of the district. Some say it looks like a praying mantis. One judge compared it to a "broken-winged pterodactyl."
This nonsensical border is widely considered one of the nation's most egregious examples of gerrymandering, in which legislators manipulate the boundaries of a district to favor one political party over another. North Carolina's 12th Congressional District was another notorious case, but gerrymandered districts exist all over the United States. This redrawing business often ends up cordoning off minority groups, and has drawn a lot of criticism. Some even call it election rigging.
In the case of this region, it's the Democratic party that holds power. Though courts found the district's borders to be constitutional and a 2012 referendum vote failed to call for a redrawing of the district, many Marylanders have protested the scattered district. For now though, the 3rd District remains.