At a (then) whopping play time of 3:10, 'Ticket to Ride' from their 1965 album 'Help!' was the first Beatles song to overstep the three minute mark. It may seem trivial now, but in the mid-60s it was a big deal because to release a single longer than three minutes meant it stood a big chance of not being played at all.
This is because most pop radio stations had a standard two-and-a-half or three-minute time limit per song. Radio back in this era was formatted to support these "bite-sized" songs as part of their strict timetables, compared to today's more open ended policy. The Beatles helped this evolution, constantly pushing the time barrier – 'Hey Jude' in 1968 was over seven minutes, and it still topped the charts!