Zooloretto: Building Sites is the expansion that adds a splash of drama to your zoo. Released in the May 2007 issue of Spielbox magazine, it provides nine construction tiles – three fences, three stalls, and three barns – that can be placed on the board to block opponents' spaces. By using these tiles strategically, you can prevent a rival from completing valuable areas and thus cut down their scoring potential. The tile‑placement mechanic blends with the set‑collection core of the base Zooloretto, forcing you to think not only about your own park but also about how you’re hindering others. Each construction type has a visual and tactical effect: fences can isolate zones, stalls create animal‑breeding spots, and barns block delivery paths. The components match the base game's graphic quality, featuring colorful illustrations and sturdy paper pieces. Playtime stays around 45 minutes, supporting 2‑5 players just like the original. With a light rule weight (1.5/5), the expansion is easy to pick up yet offers enough depth for planners. If you already enjoy Zooloretto and want a more aggressive way to interact with friends, Building Sites delivers the right amount of sabotage without overcomplicating things. Note that, as an expansion, it requires the base game to be usable. In short, it’s a compact add‑on that can completely reshape the game’s dynamics, making each round more unpredictable and fun.