Runway 30-Left is the most heavily used runway at the Minneapolis St. Paul International Airport, one of the busiest airports in the world. Runway 30-Left has historically been a critical runway since its 10,000 foot length was the longest at MSP. The runway is situated such that there is a steep slope leading from the southeast end of the runway down to the Minnesota River. The airport needed to maintain a set of strobe lights to assist aircraft who were landing in fog or other types of bad weather. These lights needed to be located at a precise distance from the end of the runway, and at a precise elevation. As it happened, some of those lights needed to be placed directly above the Minnesota river. A light bridge was the only way to place those lights at the right distance from the runway and at the proper height above the river.

The aerial photo below shows the location of the Runway 30-Left Light Structure. The divided highway is Minnesota-5 on the east side of the Minneapolis St. Paul International Airport. The end of Runway 30-Left is in the upper left side of the photo, while Fort Snelling State Park is in the upper right corner.

With the opening of the new north-south runway in 2006, the strobe lights were moved to a location crossing I-494 just east of the Mall Of America. At that time, the light structure bridge was removed, and the support on the west side of the river was replaced with a free-standing tower.

The photo above was taken in the late 1980s while I was at the airport experimenting with a new zoom lens. The 2nd photo below shows the base of the light tower on the end closest to the airport. The third photo shows the post-2005 configuration. The light tower has been removed, and additional freestanding light towers have been installed. The next two photos were provided by the US Army Corps of Engineers and the State of Minnesota DNR. The final photo is a view of the new runway light towers from an overlook on the east side of the river valley.

For most of its life, runway 30 Left was known as 29 Left. The Left part means that it is the left runway of two parallel runways. The number is the compass heading of the runway less the units digit. As a result, runway 30 Left points towards the compass heading 300 degrees. So, why did the compass heading of the runway change from 290 degrees to 300 degrees in the late 1990s? The runway did not change heading. Rather, the magnetic north pole moved. In fact, it moved just enough that a number of airport runways had to be updated in a similar manner.