Justin Bieber and Selena Gomez continued their PDA tour in Washington, DC on Saturday.

Back from sunny Cabo San Lucas where they hugged, kissed and cuddled non-stop while attending a friend's wedding, the young lovebirds were still at it in the nation's capitol.

PHOTOS: Justin Bieber Gives Selena Gomez A Love Pat In Washington

On their way into their hotel yesterday, Justin was spotted grabbing Selena's tush repeatedly, and maybe it was because she was there in a bulky winter coat, but it would have seemed Selena was ignoring her goofy boyfriend....until she finally cracked a smile.

Justin is taping a musical special Christmas in Washington Sunday night.  It airs on TNT December 16.