Card fronts featured a piece of color artwork surrounded by a thick white border; there was no caption or number on the front. Card backs featured a block of text about the subject of the image, with the card title in bold, and the card number at the bottom left; the edges were surrounded by a thick border composed of single dots of ink.
The subject of this card set was the many different types of adventure available to the modern man - most of them having to do with sports, or putting one's health at risk in what would later be called 'extreme' activities such as mountain climbing or skiing.
The most valuable cards in the set are devoted to sports figures. Although, baseball, hockey, and other such major sports are (briefly) represented, there is a healthy sampling of popular boxers of the time. The most valuable card in the set is Max Schmeling, the German champion: his card depicts him with a Nazi swastika behind him. Therefore, this set is made much more difficult and expensive to obtain due to its gaining the interests of boxing and Nazi memorabilia collectors.
In the United States, the Adventure set was issued one card at a time with one gum ball, for one penny, in a small box; in this way, kids were able to pick and choose which cards they wanted, and it's a fair bet that they mostly chose the sports figures first. In Canada, it was distributed by World Wide Gum.
Note: the set is often priced without the Schmeling card (#86), which can often command roughly half the total.