Here’s a terrific old photo from 1917 of the British Embassy, which was located at 1300 Connecticut Ave. NW, just above N St. and across the street from the Starbucks today (everything is across from a Starbucks). This was the first building in Washington built specifically to be an embassy.
Source: Library of Congress
You can see the embassy on the map below.
And here is the same intersection today on a Google Map.[googlemaps https://www.google.com/maps/embed?pb=!1m14!1m8!1m3!1d3104.7192505708513!2d-77.0426729!3d38.907534999999996!3m2!1i1024!2i768!4f13.1!3m3!1m2!1s0x89b7b7c7850cf78d%3A0xb191612931422681!2s1300+Connecticut+Ave+NW%2C+Washington%2C+DC+20036!5e0!3m2!1sen!2sus!4v1410052745684]