Ernie's camp souvenirs
Ernie returns home from Camp Winnewonga in Sesame Street Episode 1048. Ernie brought back many things from camp, which he showed to Bert, including a bird's nest, a bottle of water (with plastic fish), some rocks and a paper clip.
While Ernie refers to it as Camp Winnewonga, Bert refers to it in an earlier scene as Lake Winnewonga.