TITLE: Showing $\pi_1(M) = F$ ($F$ a finitely generated free group and $M$ an $n$-manifold of dimension greater than $2$)
QUESTION [5 upvotes]: Problem: Let $F$ be a finitely generated free group.  Prove that there is an $n$ manifold, $M$, $n > 2$ with $\pi(M) = F$.


Let $F = F_S$ s.t. $|S| \in \mathbb{N}$.
If I could show that there exists $n$-manifolds $M_1, \ldots , M_k$ s.t.
\begin{equation}
\tag{*}
F_S = \pi_1 (M_1) \ast \pi_1(M_2) \ast \ldots \ast \pi_1(M_k)
\end{equation}
then I could use the result from this post to assert that
$$
F_S = \pi_1 (M_1) \ast \pi_1(M_2) \ast \ldots \ast \pi_1(M_k) = \pi_1(M_1 \# M_2 \# \ldots \# M_k)
$$
so that if $M_1 \# \ldots \# M_k = M$, then we would have that $F_S = \pi_1(M)$ as desired.

Unfortunately, I'm not sure how we could show $(*)$, or if this is the right track towards an answer.

REPLY [5 votes]: Since both answers here give non-closed manifolds as their examples, the following realizes your question for closed $n$-manifolds.
Fix $n>2$. Then $\pi_1(S^{n-1})$ is trivial, and thus (since the fundamental group of a product of spaces is the product of their fundamental groups) $\pi_1(S^1 \times S^{n-1}) = \mathbb Z$. Write $X_1 = S^1 \times S^{n-1}$. As mentioned above, because $\pi_1(S^{n-1})$ is trivial, an application of Van Kampen's theorem shows that $\pi_1(A \# B) = \pi_1(A) \ast \pi_1(B)$ when $A$ and $B$ are manifolds of dimension greater than 2. As a result, inductively defining $X_k = X_1 \# X_{k-1}$, we see that $\pi_1(X_k)$ is the free group on $k$ generators, where $X_k$ is a closed (compact without boundary) $n$-manifold.