Google Static Maps APIで使える URLの長さの制限

Google Static Maps API - Google Code

Static Map URLs are restricted to 2048 characters in size. In practice, you will probably not have need for URLs longer than this, unless you produce complicated maps with a high number of markers and paths.

アイコンをたくさん表示しようとしたら超えちゃうかも。特にカスタムアイコンとか？
.