If you remember my April Fool's Day post from this year, then the picture below might worry you that someone decided it was a good idea.
But that there is a working trike that is used on the new Montgomery County water tunnel. "Inspectors use this bike when they need to travel along the pipe route, which is 5.3 miles long."
The tunnel, at a depth of 90 to 200 feet below the surface, depending on topography, runs between Interstate 270 in Rockville and the Church of Jesus Christ of Latter-day Saints’ Temple in Kensington.
There's another photo at the article that has the bike off to the left-hand side. Thanks to WillH for the heads up.