Mr. Ambulando is at the intersection of $5^{\text{th}}$ and $\text{A St}$, and needs to walk to the intersection of $1^{\text{st}}$ and $\text{F St}$. There's an accident at the intersection of $4^{\text{th}}$ and $\text{B St}$, which he'd like to avoid. 

Given that Mr. Ambulando wants to walk the shortest distance possible, how many different routes through downtown can he take?

Let's think step by step and output the final answer within \boxed{}.
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