Someone messaged me back to say she also blades in the DC area. In front of the White House is kind of convenient. Rock Creek Park has real paths. Hains Point is also pretty convenient. Looking for blading partners - a great dry weather activity, and not only warm weather. I've been meaning to book an inline tour trip. There's one up in Penna through part of Lancaster County. There's another literally skating across the Netherlands, but currently not in my budget. How about skate spots in Philly or elsewhere close by? Boston or NYC could be interesting for 2-3 days if planned well ahead.
There is a 12.5 mile trail around BWI airport. I know it can be accessed from the International Terminal but I’m sure it can be accessed from other places as well. I've never skated there but I know several skaters that use the trail.
The Schuylkill River Trail in Philly is a terrific place to skate. It starts from the Perkiomen Trail and goes all of the way to Philly’s Art Museum (of Rocky fame). I believe that in Manayunk there is an unpaved canal tow path but I’ve never skated to Manayunk. I usually park at the Betzwood picnic area and head left on the trail to the Perkiomen trail head and then backtrack and head towards Philly. My usual skate was a little less than 20 miles round trip.
Philly’s Fairmont Park is another popular skate. It is an 8 mile loop and also goes by the Art Museum and along the Schuylkill River. They used to close Kelly Drive, part of the loop, to car traffic on Saturday (Sunday?) mornings but I’m not sure if they still do this. It's a nice skate.
Philly also has the Landskaters in-line club. I have only gone on the slower recreational city skates which meet at the Art Museum on the first Sunday of the month. The group is friendly and welcoming to new or occasional participants.
Most of my long skating now is in Lewes, Delaware since my in-laws live there. You can park at the high school and head over the bridge, turn right onto Cape Henlopen Drive and head past the ferry and then continue into Cape Henlopen State Park, which has beautifully maintained paved trails. After hitting all of those trails, I then head out of the park, past the ferry and past the first bridge, make a little jog at Dairy Queen and then onto Cedar until it dead ends at the river inlet. I then backtrack, head over the Rt 9 drawbridge and turn right onto Pilot Town Rd and skate down to inlet again. From there I frequently cut through Pilot Town until I get to the Village of Five Points and skate around there until I eventually head back on either Gills Neck Rd.or Kings Highway to the high school. I’ve never mapped it but I would think it would be 20-25+ miles of flat nice pavement. There are enough bicyclists that cars give you respect in the few areas where there is not a wide shoulder (Pilot Town). Rehoboth Beach gets too much traffic for me to feel safe skating there.
Where I live the main roads aren’t suited for skating so most of my skating now is in a local housing development. It is a nice quiet flat (flat is rare here) housing tract with virtually no cars parked on the street and very little traffic. I have a 0.8 mile loop where I skate between 6-12 miles a day. Not very exciting but at least I can skate.
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I agree that inline skating doesn't have to be a warm weather activity. I'll head out if as long it is in double digits. Single digit temps, which fortunately are rare here, I avoid because my toes get too cold. Instead of skating, I hike and geocache in singe digit temps.