Yesterday I tried tacos at two Bladensburg Taquerias. The best were at Taqueria La Placita on Edmonston. We had the Pastor and Carnitas. The Carnitas were a bit bland, but the Pastor were awesome. They are cooked with pineapple on the rotisserie. The also had nopalitos and various tacos that either I hadn't heard of or new what they were but am not adventurous enough to try. They had ear, belly and tripe tacos. They also had barbecued lamb tacos which I didn't see on the wall menu but did see on the printed menu after we ordered. The salsas were good. They didn't seem to have any fresh agua frescas, only bottled.
Taqueria Tres Reyes II was also good, but not as good as Las Placitas, especially the Pastor. However, they have better salsa and home made agua frescas.
There are two other taquerias that I haven't tried on Edmonston (Taco Rico and La Azteca). There was also a taco truck in someone's front yard, but they had only one customer.
In front of La Placita, there was a van selling roasted corn out the back. I didn't try it, though it looked good, because we were searching for tacos only.
If you want authentic Mexican tacos, go to Bladensburg. They are cooking for a Mexican audience. You may need to know a little Spanish to order, but it is worth it.