In 1970 Hull Harriers joined forces with Hull Achilles and took on the name of City of Hull Athletic Club. The club gained the membership of Bob and Pam Piercy, English international 800 metre runners who gave a terrific boost to the track athletics. After amalgamation the club had a substantial Ladies Section. In some respects the choosing of the new name meant that the wheel had turned full circle, for many of the club's founding fathers had been members of the long defunct Hull Athletic Club.
During the 1960s and the 1970s, many of the club’s athletes made their mark including Pete Collinson, Peter Chapman and Barry Short. The first half of the 1970s were also a time of great success for the Boys, Youths and Junior teams coached by the two Petes, Jarvis and Chapman. Martin Farrall, Steve Rennie, John Devaney, K. Hodsman, Steve Scargill and Barry James all date from this era. The boys won a string of team events in 1970 including the Yorkshire Championships when Ray Cocks took the individual title, after taking the lead in the two mile event at the halfway stage. They finished second to Sale in the Northern Cross-Country Championships held at Blackburn, well ahead of Middlesborough the third placed club. The club took the Yorkshire Youths Championship in 1973 and Cocks took the individual title. The team went on to win the Northern Youths title at Blackpool, finishing 35 points ahead of their closest rivals Liverpool Harriers. In that race Cocks finished second whilst Steve Rennie and Steve Scargill finished ninth and eleventh respectively. In 1974 City of Hull’s Youths and Junior teams both finished third in the English Championships which attracted more than 2000 runners whilst the Juniors took the Yorkshire Junior Championship title in 1974. The following year the Juniors not only took the Yorkshire Championships again (Malcolm Prince, Steve Rennie, Ray Cocks and John Devaney) but finished second in both the Northerns and National Cross-Country Championships. The counting team members in both of these races were Malcolm Prince, Ray Cocks, Steve Rennie and Steve Scargill.
Throughout this period many of the youngsters achieved individual representative honours. Carl Nightingale, John Devaney, Steve Rennie, Steve Scargill, Barry James, K. Hodsman and Martin Farrell all represented Yorkshire at one level or another. But although there was much individual success the emphasis was always on team spirit and a hard training regime which at one time prompted one newspaper to ask if City of Hull A.C. had the fittest youngsters in England. Many of them went on to become exceptionally good club runners at Senior Level and some such as Steve Rennie and Martin Farrall won a number of club, local and regional races over the following years. Ray Cocks’s pinnacle was being awarded his international vest as first reserve for the England under 19 team for the international cross-country championships at Monza in Italy. However, Malcolm Prince enjoyed the greatest success as a Senior becoming a full international. Malcolm won an impressive range of representative honours and major titles and, whilst still a sixteen year old, he set a world best performance for that age in the 10,000 metres when he recorded a time of 31 minutes and five seconds in finishing second to Barry Short in the club’s 10,000 metre Championship at Costello in 1972.
The fixture cards covering the 1898/9, 1927/8 and 1970/71 seasons give some indication of how activities had widened by the 1970s. By the latter year, of course, the club has become City of Hull Atletic Club. In that year the traditional First and Final Runs of the cross-country season were still being held, but these soon ceased. The 1970/1 fixture card belonged to Reg Taylor, a President on the club.
Malcolm Prince and Ted Coggin both became full internationals whilst members of the club. Great Britain international Jim Dingwall captained the Scottish cross-country team whilst club captain and in the late 1980s Dominic Gibbons, Tanya Blake, Andy Gill and Jeanette MacLean brought honour to both club and city by winning junior international vests for track and field.
From the beginning of the 1980s the club benefited from the "Running Boom" which saw thousands of people take up – or return – to running at this time. Amongst the runners who joined the club in this period were the Slater brothers, George, Tony and Phil. George went on to become club captain. Others included Alan Fowlie, Gordon Jibson, Dave Brooke, Phil Groves, John Matthews, Terry Davis, Ian Adams, Robb Robinson, Frank Harrison and, later, Mike Baggott and Pete Blowers. A small cohort of women also came to the fore during this decade and enjoyed a substantial degree of success on the road country and track both locally and on the wider stage. They included Denise Briggs, Ann Sweeney and Jeannie Coupland. Denise and Jeannie are, of course, daughters of well known club members, Dennis Briggs and Bob Coupland, but made a substantial mark in their own right.
The number of races available across the country mushroomed during this decade with a large number of marathons and half marathons, as well as 10 mile and 10K road races attracting substantial fields. Runners from the club were usually competing far and wide across the north of England and beyond on many weekends.