By Metro/Bus
The quickest way to get to downtown Kensington and Antique Row is usually to take the metro and then transfer to bus. RideOn Bus 5 (http://www.montgomerycoun...) from the Silver Spring Red Line metro stop is the most convenient option, which will take you straight to Antique Row, making stops near the Mormon Temple, as well as downtown Kensington. Because of the transfer, this trip is longer than taking the light rail, but you can rest easy knowing that you won't get stranded!
If coming from the northwest branch of the metro's Red Line, get off at the Medical Center stop and take RideOn Bus 34 (http://www.montgomerycoun...) towards Aspen Hill, which will take you right through the center of Kensington where you can transfer to the #5 and on to the Wheaton Metro stop. This bus originates in Friendship Heights and passes through Bethesda before reaching Medical Center.
By car
The main arteries leading north from Washington, D.C. and the Beltway are Connecticut Ave and Wisconsin Ave. Connecticut will take you straight through the center of Kensington—turn right at Strathmore/Knowles Ave and follow it to the end to get to Antique Row.
Despite being so easy to see from the Beltway, the Mormon Temple is quite difficult to find. The easiest and most navigable path is to take Beach Drive east from Connecticut Beach Drive is just north of the Connecticut Ave Beltway exit.
If you take a taxi from D.C., be aware that your driver may not know his/her way around Maryland. So bring directions to help the taxi driver out! If it's after midnight, taxis hate crossing the district line, and you could wind up waiting hours on either side after making the call.
By Rail
Public transportation to Kensington is underwhelming compared to its neighbors. The most charming mode of arrival is without a doubt the MARC train Brunswick line from Union Station, which will take you directly to the historic train station in the middle of Antique Row. The downside is that the light rail runs infrequently during off-hours non-rush hour, and quite infrequently when traveling in the opposite direction of rush hour.