Question: What is the biggest chocolate model of a series of fortifications made of stone, brick, tamped earth, wood, and other materials, generally  built along an east-to-west line across the historical northern borders of china  housed at World Chocolate Wonderland?
Sentence (from "World Chocolate Wonderland"): Located in Beijing to the north of the Bird's Nest, its grand opening was on January 29, 2010.
Relevant evidence: No