We study existence and convergence properties of least-energy symmetric solutions (l.e.s.s.) to the pure critical problemwhere s is any positive number, Ω is either R N or a smooth symmetric bounded domain, and D s 0 (Ω) is the homogeneous Sobolev space. Depending on the kind of symmetry considered, solutions can be sign-changing. Once existence is established, we show that, up to a subsequence, a l.e.s.s. us converges to a l.e.s.s. ut as s goes to any t > 0 (possibly an integer). In bounded domains, this convergence can be characterized in terms of an homogeneous fractional norm of order t − ε. A similar characterization is no longer possible in unbounded domains due to scaling invariance and an incompatibility with the functional spaces; to circumvent these difficulties, we use a suitable rescaling and characterize the convergence via cut-off functions. If t is an integer, these results describe in a precise way the nonlocal-to-local transition. Finally, we also include a nonexistence result of nontrivial nonnegative solutions in a ball for any s > 1.