Batting first, Dolben piled on the runs and eventually closed on 321-4 from their 50 overs.
A third-wicket stand of 181 between captain Drew Brierley (118) and Callum Berrill, who batted throughout the inning for an unbeaten 98, proved crucial.
In reply, Peterborough gave it a real go with David Clarke (76) leading the way.
But he was one of Brierley’s (3–59) victims as the Dolben skipper completed an excellent individual display and, with Mark Wolstenholme and Tom Brett picking up a couple of wickets apiece, Peterborough were bowled out for 279.
Geddington remain in contention at the top end of the table as they thrashed struggling Brigstock by 171 runs on what proved to be a landmark day for Andrew Reynoldson.
The Geddington batsman struck 81, which helped take him past the 10,000 run mark in county league cricket.
Patrick Harrington (64) and Jack Parker (54) also made good contributions as Geddington closed on 278-8 with Harry Howell (4-57) and Tashwin Lukas (3-41) the pick of the Brigstock bowlers.
But it proved a real struggle in reply as Brigstock were dismissed for just 107 as Jafer Ali Chohan (3-20) and James Gaul (3-43) starred with the ball.
Brigstock are now bottom of the table after a crucial clash went the way of Rushden & Higham Town who beat Desborough Town by 14 runs.
Batting first, Rushden put a big total of 268-7 on the board with Steve Materna (75) and Ross Cunningham (66no) sharing a stand of 123 for the sixth wicket.
In reply, Simon Renshaw (72), Rohin Thapar (54) and Will Sercombe (46) all scored well for Desborough but they fell short on 254 as Chris Law (4-47) and Cunningham (3-32) bowled Rushden to a vital win.
Another high-scoring encounter saw Oundle Town lose out to Overstone Park.
Not for the first time, James Sales (86) and Harry Gouldstone (80) helped lead Overstone to a big total of 285-9, despite the efforts of Will Park who claimed fine figures of 9-0-56-6.
Sam Jarvis (58) and Tommy Simeons (51) both struck half-centuries for Oundle but their reply fell short as they were bowled out for 254 with Benjamin Sales (3-47) the pick of the Overstone bowlers.
The other game of the day in the top flight saw Old Northamptonians (284-8) maintain their climb up the table with a 17-run success over Kislingbury (267).
Amrit Basra was the all-round star for ONs as he top-scored with 68 before taking 3-61 with the ball.
New leaders Dolben head to Short Stocks to take on Rushden & Higham this weekend while second-placed Peterborough are also on the road at Overstone Park.
Geddington have home advantage as they play Kislingbury and Oundle make the trip to play in-form ONs.
The other game is a big one as bottom side Brigstock entertain third-from-bottom Desborough.
Burton Latimer closed the gap at the top of Division One as they won the big game of the weekend at leaders Loddington & Mawsley.
And it ended up being a fairly straightforward success for Burton thanks to their overseas star Charitha Kumarasinghe as he blasted an unbeaten 148 from just 91 balls to lead his team to an eight-wicket victory on 235-2.
Earlier, Loddington had been bowled out for 232 with Ben Roughan (46), James Coles (42) and Ryan Richens (41) all scoring well while David Shelford (3-23) and Niall Ferry (3-62) were the pick of the Burton bowlers.
Brixworth remain firmly in the promotion hunt after they beat struggling Weekley & Warkton by 35 runs.
Henry Timm top-scored with 78 as Brixworth put 293-9 on the board, despite the efforts of Jack Issitt (9-1-52-5).
In reply, Jacob Palmer struck 67 for Weekley but they eventually fell short on 258-8 as Toby Cowley (3-39) performed well with the ball for Brixworth.
Elsewhere, another game between two promotion contenders saw Wollaston claim an important win over Wellingborough Town.
Harry Dolan cracked 103 as Wollaston piled on the runs to close on 307-6 from their 50 overs.
And then Chris Perry took 4-46 as Wellingborough were bowled out for 215 in reply.
Loddington hold a seven-point lead over second-placed Burton with Brixworth a further three adrift while Wollaston and Wellingborough are still in the hunt.
This weekend see Loddington taking on Stony Stratford while Burton host Brixworth in a crucial clash.
Great Houghton took the glory on the Hevey T20 Plate Finals Day.
Houghton started the day by edging out Irthlingborough Town by 10 runs in their semi-final clash.
The other last-four encounter saw hosts Wellingborough Town claim a comfortable eight-wicket success over MK Air.
But it was Division Three side Houghton who took the silverware as they defeated Division One outfit Wellingborough in the final.