If you are looking for engagement rings in DC, there are a number of DC jewelry stores and Northern Virginia jewelry stores that offer plenty of wonderful trinkets in this vein to choose from. However, not all jewelers Washington DC and its environs have to offer are necessarily alike in price, quality, or style, so it does help to know what your budget might be and what style of engagement ring you have in mind before going forward. The traditional diamond ring is still as popular as ever, but plenty of other styles, stones, and more are available as engagement rings in DC and elsewhere.
Once you have set your style and budget, search the web for jewelry stores in dc, Northern Virginia, and jewelry stores in Maryland that carry the type of thing you have in mind. Search the web for reviews of Washington DC jewelers in the vein you are looking for, and then take a look at the items for sale at each facility. Choose the loveliest ring that you can reasonably afford, and hopefully your sojourn through the various providers of engagement rings in dc proves to be worth it in the end!