Race Information

Stone Mill 50 will be held on Saturday,Nstonemill revisedov 14 2015 at 6am. Registration to open August 1st here

<30 spots available

Stone Mill has been selected as the RRCA Maryland State 50 Mile Championship for 2015


TRAINING RUN ON 10/11 at 7:30 AM –Riley’s Lock


2015 Course: The WSSC work plan near the trail is now definite and we can finalize the 2015 course. It will be mostly the same as in 2014 with a couple of minor changes.

Removed from last year:the initial out and back to Brink Road. 2.8 miles

New this year:Long Draught Trail near Riffle Ford Road each way. This will add 2.3 miles

Don’t worry,the total distance is still 50 miles (and a little more)

Map Coming soon…


2014 Results here

To Volunteer Click Here

The Stone Mill 50 Mile is a 50 mile trail run on the Seneca Greenway and Muddy Branch trails in Montgomery County Md. The course traverses forested,rolling terrain. The course is primarily on single track dirt. There are small stream crossings. Most of the course drains well,but parts can be muddy in wet weather.

Host Hotel:

The Comfort Inn Shady Grove in Gaithersburg will again be the host hotel with a discounted nightly rate of $94. call the hotel to make a reservation and ask for the Stone Mill rate.

16216 Frederick Rd.,Gaithersburg,MD,20877

301 330 0023


Parking near start/finish area

Parking at Stedwick ES is limited. There is street parking on Watkins Mill Rd,Apple Ridge Rd,and a few other lots. Please consider carpooling. There is a large park and ride at Exit 11 on I-270

When 6AM Start

The Stone Mill 50 Mile run will start at 6:00 AM on Saturday November 14,2015. The cut off time is officially 13 hours or 7:00 PM,and will be strictly enforced due to permit requirements and so we can let our amazing volunteers go home. Intermediate cutoffs are

6PM to Rt 355 Aid Station, 4 miles to go

4:45PM to the Riffleford Rd Aid Station, 9 miles to go

2:45PM to the Rt 28 Aid Station,17 miles to go

1:30PM to the Stone Mill,23 miles to go

Where Start/Finish Stedwick Elementary School

The start/finish will again be at Stedwick Elementary School 10631 Stedwick Road, Montgomery Village,MD 20886
The course will follow Watkins Mill Road for 1/2 mile to and from the trailhead.

Training Runs

No aid,no water,no markings –but there will be 3 training runs along the course for folks that want a preview.

Sun 10/11,7:30AM from Riley’s Lock (UPDATED LOCATION) Lower Greenway

Sat 10/17,7:30AM from Pennyfield Lock off River Road –Muddy Branch Trail

Sat 10/24,7:30AM from Watkins Mill HS- Upper Greenway

Packet Pickup
Friday 11/13 at the host hotel,4:30-7PM.

You can still pickup your packet on race day at the starting area if you can’t make it on Friday,but get there as early as possible (by 5AM).

Refunds and Bib Exchanges: It’s just not practical to process refunds or bib exchanges. If you decide to withdraw from the race please email Barry &Daryl and your entry fee will be donated to the State and County parks instead of buying more stuff for the aid stations.

Pacers: Sorry,no pacers.  Our permits with the various park services have a strict limit on the number of runners so we can’t allow  pacers.