What is this?
tree trunk
beaver dam
nest
arch
What is this?
bridge
cave
arch
pillar
What is this?
skeleton
eggshell ( shell )
cave
nest
What is this?
nest
cave
beaver dam
arch
What is this?
shell
skeleton
ladder
tree trunk
What is this?
basket
castle
stairs
ladder
What is this?
ladder
bridge
arch
castle
What are these?
stairs
bridge
pillar
ladder
What is this?
arch
pillar (column)
stairs
castle
What is this?
pillar (column)
bridge
castle
arch
What is this?
bridge
house
arch
castle
What is this?
tree trunk
tree house
tree branch
tree root
What is this?
eggshell
shell
nest
cave
What is this?
book
bag
basket
box
What is this?
box
basket
bag
book
What is this?
cave
pillar (column)
tent
arch
