[OldMissileer]

Not so. All of I-66 inside the Beltway now converts to toll/HOV during each 4-hour rush hour period.

I should have prefaced my reply by writing about being outside the Beltway. Inside has been HOV for years if I remember, but I almost never used it so I may be wrong.

[Interesting Times]

I-66 outside the Beltway is still free, but is planned for toll/HOV conversion in a couple of years. You might be thinking of I-495 in Virginia, which has parallel toll/HOV and free lanes.