Greatest Blossom Music Center concerts: No. 8 – Blood, Sweat & Tears

Traffic woes at Blossom Music Center have long been documented — but Blood, Sweat & Tears' 1969 concert was on a whole different level.

Why it matters: The show drew a crowd of nearly 25,000 people and still holds the attendance record for a single concert at the venue.

Flashback: Blossom started hosting rock and pop concerts in the summer of 1968, featuring performers such as Judy Collins, Vanilla Fudge and Tony Bennett during the first year.

• Blood, Sweat & Tears' Aug. 26, 1969 show came one week after their performance at Woodstock, making it one of the most anticipated events of the summer.

The intrigue: The festivities got off to a rocky start with traffic backed up more than a mile from Blossom.

• Among those stuck were the members of Blood, Sweat & Tears, who — like most fans – parked their vehicle on the road and walked to the venue while carrying their instruments.

State of play: Those who made it to Blossom early were able to catch the opening act — a mostly unknown John Denver, who had just left The Chad Mitchell Trio to focus on a solo career.

• Blood Sweat & Tears took the stage three hours after gates opened, delivering a lively setlist highlighted by originals like "More and More," as well as covers of songs by Traffic, Laura Nyro, Joe Cocker and others.

Between the lines: Some estimates have put attendance at closer to 30,000 people, many of whom entered the grounds without tickets by sneaking through the woods nearby.

The bottom line: That led to the construction of a fence to prevent a repeat occurrence, solidifying Blood, Sweat & Tears as a singular event in Blossom's history.

Go deeper: No. 9 — Lollapalooza 1992