|Macintyre, Ben (2014-07-29). A Spy Among Friends: Kim Philby and the Great Betrayal. Crown Publishing Group. Kindle Edition.
The British embassy was in secret uproar as news spread that not one but two senior Foreign Office officials in Washington had vanished and were probably Soviet spies. Philby and Paterson together broke the embarrassing news to the FBI. Philby carefully observed the reaction of his FBI friends, including Bob Lamphere, his former dinner-party guest, and saw only surprise, tinged with some wry pleasure at the British predicament. So far Philby himself did not seem to be under suspicion. At lunchtime Philby told Paterson he was going home for “a stiff drink,” behavior that anyone who knew him would have considered perfectly normal. Back at  Nebraska Avenue, Philby headed not for the drinks cabinet but for the potting shed, where he collected a trowel, and then down to the basement that had, until recently, housed Guy Burgess. There he retrieved from a hiding place the Russian camera, tripod, and film given to him by Makayev, sealed the lot in waterproof containers, and placed them in the trunk of his car. Then he climbed in, gunned the engine, and drove north. Aileen was at home with the children; if she thought it strange that her husband should come home from work early, lock himself in the basement, and then drive away without a word, she did not say so.
Philby had traveled the road to Great Falls many times. Angleton had taken him fishing in the Potomac Valley and there was a faux-English pub called the Old Angler’s Inn where they had spent several convivial evenings. The road was little used and heavily wooded. On a deserted stretch with woods on one side and the river on the other, Philby parked, extracted the containers and trowel, and headed into the trees. He emerged after a few minutes, casually doing up his fly buttons for the benefit of any passersby, and drove home. Somewhere in a shallow hole in the woods beside the Potomac lies a cache of Soviet photographic equipment that has lain buried for more than sixty years, a secret memorial to Philby’s spy craft.
4100 Nebraska Avenue, NW, Washington, DC
Potomac River Great Falls, VA and MD