I like to include the custis trail as part of what I call the "bicycle beltway". I start at the Eisenhower connecter beltway exit at the clermont access bicycle ramp. Next its on to the cameron run trail toward ramsey nature trail. from there its thru the neighborhood of seminary hills and onto walter reed dr. and the four mile run trail. next its the W & OD trail and right onto the custis trail. Then south on the Mt. vernon trail and finally west thru old towne to the cameron run trail and back to clemont. total miles: 28. perfect after work night ride or weekend afternoon ride!

The section of this trail from Theodore Roosevelt Island / Rosslyn to about Glebe Road is almost all up hill. The first mile or two from Rosslyn to Veitch Street is a just wide sidewalk. The total vertical rise from Rosslyn to Glebe Road is about 300 feet. This section is a good workout for those who like hills. To the west of Veitch Street, It runs along side Interstate 66 but is separated from it. There are some nice woods along this portion but it is always noisy because of the interstate.

This trail was originally a rail trail which followed a spur of the Washington and Old Dominion Railroad (W & OD) from East Falls Church near the intersection of Lee Highway and Washington Boulevard. I rode the portion from Rosslyn to North Kirkwood Road in the early 70's. Later Interstate 66 was built along the old railroad right of way. The current trail runs along side the Interstate.

A friend and I just rode the loop that mdcrtse described in his June 18, 2009 review but started about a half mile south of the intersection and Mount Vernon trail and the Four Mile Run Trail. We parked at Dangerfield Marina, took the Mount Vernon trail north to the beginning of the Custis trail near Theodore Roosevelt Island. Then we followed the Custis trail to the W&OD trail. After that we took the W&OD trail to its end in Shirlington. Finally we shifted over to the Four Mile Run Trail and followed it back to the Mount Vernon Trail.

This route puts almost all of the uphill in the first half of the trip, followed by a gentle down hill return to the start. If you like hills, pick up the Four mile run trail as soon as you encounter it. Although it runs parallel to the Four mile run trail, it has many small and medium size hills and one large one.

This trail is a nice trail for those who like going up and down hills. If you start at the Theodore Roosevelt park (on the Potomac river) you climb up a very long hill on a side walk marked with an orange stripe designating the trail. After you get past the first long (and steep hill) you go down and up quite a bit as the trail follows route 66 and climbs from road level up to overpass bridges and roads. Unfortunately you will not be rolling down hill coming back as the trail goes up and down in both directions. Although it will be a long down hill going west to east when you get near the Potomac.

I recommend this trail as the beginning of a 18 mile loop. Beginning at the Roosevelt Island parking lot climb up past the Marriott and follow the trail to the W&OD trail. Take the W&OD trail south past Bluemont park. Note if you don't see the Bluemont park after a riding on the W&OD trail for a mile then you are going the wrong direction. After riding 4 miles the W&OD trail ends. Follow the signs across the street and to the right to pick up the 4 mile run connector and follow it down to the Potomac where it connects with the Mt. Vernon trail. It is a little tricky here because you actually pass under the Mt. Vernon trail before curving around to connect with it. Turn right and ride past the Reagan national airport. Continue along the Mt. Vernon trail as it follows the Potomac river back to the Roosevelt Island park. All in all the loop is 18 miles with the most strenuous riding occuring along the Custis trail (especially the beginning section riding up the hill past the Marriott Hotel.)