I have $n$ points $p_i$ strictly interior to a rectangle $R$, and I would like to connect them with a curve $C$ whose curvature is as low as possible. Let $\kappa_\max(C)$ be the sharpest (largest absolute value) of the curvature of $C$ at any point along $C$. More specifically, $C$ should: (a) pass through the points *in any order*; (b) be simple, i.e., non-self-intersecting; (c) remain inside $R$; and (d) have the minimum $\kappa_\max(C)$ over all $C$ satisfying (a,b,c). For example, perhaps the curve left below is optimal. The right curve has lower curvature but strays exterior to $R$. <br /> <img src="http://cs.smith.edu/~orourke/MathOverflow/BoundedCurvature.jpg" alt="B oundedCurvature" /><br /> I am seeking a lower bound on the minimum of $\kappa_\max$, as a function of the point configuration and its placement within $R$. I have seen literature bounding curvature *variation*, and literature focused on *shortest paths* of bounded curvature, and literature that permits $C$ to self-cross, but no literature on my specific collection of constraints. My $n$ is not large, so a solution for a fixed permutation would still be quite useful. If anyone can point me to relevant literature, I would appreciate it. Thanks! <b>Addendum</b>. Here is what I gather must be Anton Petrunin's idea: <br /> <img src="http://cs.smith.edu/~orourke/MathOverflow/BoundedCurvatureAnnulus.jpg" alt="BoundedCurvature" /><br /> And here is Scott Carnahan's improvement to my example, left: <br /> <img src="http://cs.smith.edu/~orourke/MathOverflow/BoundedCurvature1.jpg" alt="Improvement" />