Old Pass Hill is located between Old Blewett Pass and Blewett Pass. The route offers beautiful panoramas of the Teanaway peaks Tronsen Ridge, but even with a decent snow pack, the slide alder that grows on disused logging roads can add difficulty to a trip to the summit. Like nearby Cairn Hill, this peak is on the exposed east side of the Cascades, so it's best to avoid on particularly cold days.
It's best to begin from the Blewett Pass Sno-Park and then cross the highway (carefully of course). That way your car is off the highway, and protected from other traffic. Once across the road, look for the route, which follows Scotty Creek Road (Road 7324). Take this trail, groomed for snowmobiles and hike just under a half mile, where you will join the cross-country ski or snowshoe trail.
Stay on this road, passing Cairn Hill to the left. After three miles you will reach a saddle on Old Pass Hill. At this point, simply remember to always choose the high roads, which will eventually lead you to the summit. On the way, you'll enjoy views of the surrounding areas, including the Enchantments and, if you're lucky, a peek at Mount Stuart. Blue blazes on the trees alongside the trail should also help you navigate, but do be sure to refer to your map if you are unsure.
Because this route may have unstable snow, travelers should always be fully equipped with avalanche gear, and should always check the conditions before heading out.