Baseline and Principal Meridian

Today I tried to find the Baseline and Principal Meridian at Monument Hill in Avondale (Real Estate Professionals will understand), but was only left with a closed gate entrance next to the NASCAR racing track or a path leading to a fishing location. I did see a bit of the Gila River though on S El Mirage Rd, followed by the planes at Phoenix Goodyear Airport – better luck next time.