Eric Spiegelman was at Disneyland checking out an old map of California mounted in the Main Street railroad station when he spotted an unexpected geographic feature. "There are like a thousand websites that list the hidden secrets of Disneyland, but on Saturday we found something they all missed," he posted. Actually, the unfortunately named Nigger Slough shows up on many early maps of the Gardena area — the basin, later renamed Dominguez Slough, was a pretty evident part of the pre-suburban landscape at that end of the county. Blake Gumprecht's book, "The Los Angeles River: Its Life, Death and Possible Rebirth," describes the slough as "a stagnant backwater" of intertwining channels formed by river floodwaters that backed up against the Dominguez Hills and sometimes covered as many as 7,000 acres. A while back, the blog L.A. Creek Freak offered tips for finding the old sloughs and waterways of the Los Angeles area.

* And: Jessica Hall explored the slough's history in a 2008 post at L.A. Creek Freak.