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The Kruskal-Szekeres coordinates construction for the Schwarzschild spacetimecould be viewed geometrically as a squeezing of the $t$-line associated withthe asymptotic observer into a single point, at the event horizon $r=2M$.Starting from this point, we extend the Kruskal charting to spacetimes with twohorizons, in particular the Reissner-Nordstr\"om manifold, $\mathcal{M}_{RN}$.We develop a new method for constructing Kruskal-like coordinates and find twoalgebraically distinct classes charting $\mathcal{M}_{RN}$. We pedagogicallyillustrate our method by constructing two compact, conformal, and globalcoordinate systems labeled $\mathcal{GK_{I}}$ and $\mathcal{GK_{II}}$ for eachclass respectively. In both coordinates, the metric differentiability can bepromoted to $C^\infty$. The conformal metric factor can be explicitly writtenin terms of the original $t$ and $r$ coordinates for both charts.

On the generalization of the Kruskal-Szekeres coordinates: a global conformal charting of the Reissner-Nordstrom spacetime