Century #300 3 34ish laps from Rite Aid in Concord to various parts of Alewife station via the Minuteman Rail Train from Bikeway Source in Bedford. Predicted temps of 30 in Concord at 8 AM so had to dress warmly for legs, hands, feet (plastic sandwich bag in shoe with heat pad stuck on the bag - worked FINE. Original plan was to make a short first lap and eat to let the temps rise to th mid-hi 40s for laps 2 & 3. But added some distance at Alewife that was slow THAT WAS STUPID. RIDE ONLY FAST ROADS. Came back to Dunkin - Coke, glazed, 4 egg wraps (2 for now 2 for later) After lap 1 changed out of thick SPORT HILL pants to lighter tights - both times with white leg coolers underneath. That was a good move to lessen weight as the temps rose. On lap 3 I met Karen Kaplan from Arlington on the way in. She was riding super steady, but somehow wound up in front. SHE said she had done the trail hundreds of times so I figured I should learn from that. She managed to navigate the crowds flawlessly - once I was behind her, not drafting but just going her pace, my HR droppped from hi 120s to 118 - what a relief and I didn't have to decide when to pass or whatever. She got off in Arlington Center headed down Rt 60/Pleasant St Then on the way back from Alewife about 1/2 mile out, I ran into a couple headed to the Bedford end of the trail. They had driven from Arlington and had parked there. They claimed to be new riders 10-12 mph, thinking about doing a century this year. She was super smooth - high cadence, pedaling all the time. He was big ring, small cog at 45-50. I didn't go between them and had a hard time trying to convince him that his wife had great technique he should try. I never did get contact info - unlike me. For me things worked well because I get very uniform pacing on the climbs to Arlington and Lexington.A great ride, but very tiring. The last 20 miles were much slower than before 11ish. I was beat. When I got to Concord Center at the end I had to rest before completing the final 3 miles. Had trouble dismounting and remounting the bike.