OK, this thing was surprisingly easy to find. I was expecting to be doing a grid search in the middle of a flat field but it was nothing like that.
If you have the first quarter 2007 Apex to Zenith, the map on the cover was very useful once you figured out which streets were depicted on the small map. If you don't have the A to Z issue (or even if you do), this link really helps you zero in on things:
http://www.everytrail.com/view_picture.php?picture_id=12826
In terms of directions, I'm going to use the intersection of Wisconsin and Nebraska (in the Nortwest quadrant of DC) as the main point of reference. From this intersection, which basically forms an "X", head northeast on Nebraska (driving up the upper right portion of the "X"). As you drive northeast, the first intersection you pass will be be with Albemarle St. NW. You will then pass Wilson High School and its large outdoor track/football field on your left. Next is the intersection with Chesapeake St. NW. After you pass Chesapeake, look to your left and you will see the open field for which you're looking. I passed by the field and turned left onto Fort Dr. NW, which is really just the entrance for Deal Jr. High School. As long as school is out, parking along Fort Dr. is no problem. Then just basically walk WSW up the small hill (with the Jr. High as your back and angling away from Nebraska). The 2007 marker is huge by USGS standards and is a "can't miss" type of thing.
Please note that if you're southeast on Wisconsin from I-495, you cannot turn left onto Nebraska so you'll have to figure out a way to get yourself pointing the right way on Wisconsin or make a few turns and work your way over to Nebraska. If you hit it at the wrong time, traffic can be a nightmare in this area. Off hours are best for your visit.
Also, even though the "artificial" area along the reservoir is not the true natural HP, it's not a bad idea to visit it IMO. It really feels more like the HP than where the marker is even if there is a crappy fence along the artificial "summit plateau." Lots of folks seem to do this as there is a well worn path around the fence.
Let's be safe out there.
