Is it true that given any unbounded domain $D$ strictly in $\mathbb C$ and a boundary point $z_0$, and two real numbers $R > r > 0$, I can choose some $r' < r$ and $R' > R$ such that $\{ z \in D : r' < |z - z_0| < R'\}$ is a domain?
Here an open subset of $\mathbb C$ is called a domain if any two points in the subset can be joined by gluing straight broken line segments in the subset.