。
There wasn't a long line at the stadium.
Literal
Baseball-field [at-には] long line [topic-は] not-existed.
Double は: には (locative+topic) and 列は (topic contrast). The first marks the scene, the second contrasts 'long lines' with other possible things. The implication: 'there may have been other things, but no long line.' Very Japanese in its use of は for implicit contrast.