sentences:  On the southeast side of the city, US 87 merges with Interstate 10 (I-10), where it continues through San Antonio as a co-signed, concurrent route for , until an exit at Comfort, where the highway once again picks up its own signage and continues on, in an almost due northern heading to Fredericksburg, before making a slight turn back to the northwest to Mason, where it merges with US 377.From Mason, US 87/377 continues north/northwest to Brady, where US 377 leaves the route and US 87 makes a hard turn to the west before taking yet another slight turn to the north and continuing on to San Angelo, and on to the northwest.After intersecting with I-20 at Big Spring, US 87 continues the same northwesterly path to Lamesa, where it takes a turn back to the northeast.