Ahh, the Third Street light rail (the "T-Third")...for so long just a gleam in a transit rider's eye. Well, this weekend it's going to be tested out. Which is great for people who want to ride it. But not so great for people who are looking to drive in that area because MTA will close the Islais Creek Bridge and the 4th Street Bridge to test it out.

And sadly, we spent a long time trying to do some sort of pun between those two bridges and Fergie's "London Bridge" but couldn't come up with anything. Even worse, we now have that God-awful song stuck in our head. So be nice to us today.

The Islais Creek Bridge will be closed from 7 a.m. to 5 p.m. Saturday and 7 a.m. to 12 p.m. Sunday. As for the 4th Street Bridge, that will be closed from 12 p.m. to 5 p.m. on Sunday. The 15 Third bus will also be rerouted during the weekend.

But what of the Third Street Rail? Well, believe it or not, it's pretty close to being ready to go. Next week, it'll start rolling on the weekends. And not only rolling, but rolling for free. Yep, that's right, it'll be free to ride it if you board south of 4th & King. This special offer will last til April Fool's Day. Full service starts up a week later, on April 7th.

For more info, go here and here.