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Monument Hill - B&M Wildlife Area, AZ

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Guide 12 Triplogs  0 Topics
Rated  Favorite Wish List AZ > Phoenix > Phoenix SW
3.3 of 5 by 3
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Difficulty 1 of 5
Route Finding 1 of 5
Distance Round Trip 0.6 miles
Trailhead Elevation 946 feet
Elevation Gain 215 feet
Accumulated Gain 230 feet
Avg Time Round Trip 0.5 hour
Kokopelli Seeds 1.75
Interest Historic, Seasonal Creek, Perennial Creek & Peak
Backpack No
varies or not certain dogs are allowed
editedit > ops > dogs to adjust
feature photo
Photos Viewed All Mine Following
6  2016-04-19
Tres Rios Wetlands
2  2016-02-18 gummo
5  2015-05-09 gummo
9  2013-02-01 burntlizard
15  2013-01-20 chumley
Author chumley
author avatar Guides 75
Routes 667
Photos 13,162
Trips 1,416 map ( 10,534 miles )
Age 46 Male Gender
Location Tempe, AZ
Historical Weather
Trailhead Forecast
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Preferred   Feb, Jan, Dec, Nov → 9 AM
Seasons   Autumn to Spring
Sun  6:13am - 6:34pm
Official Route
1 Alternative
Fauna Nearby
Culture Nearby
It All Starts Right Here!
by chumley

History: Arizona's Initial Point (the intersection of the base line and primary meridian now known as the Gila and Salt River Base Line and Meridian respectively) was officially established in 1865 by John A. Clark, the Surveyor General for NM and AZ. This followed the Gadsen Purchase, completed in 1854. For the previous six years (under the Treaty of Guadalupe HIdalgo), the Gila River was the international boundary between the United States and Mexico, making this small hill at the northern terminus of the Sierra Estrella Mexican territory. The point had originally been marked with a monument by a Mexican Boundary Commission crew led by Francisco Jimenez in the early 1850s. In 1867, the first survey was conducted from the initial point, covering 36 miles in 5 days.

Benchmarks: If you ever encounter survey markers around Arizona you can figure out how far you are from Monument Hill. Each Range and Township is 6-miles. So the 6x multiple of the township and range numbers stamped on the benchmark will tell you your distance from the Salt and Gila Base Line and Meridian. (There are some deviations to this system because land is not flat, but that's the basic premise). All survey marks in Arizona are established from the Initial Point on Monument Hill!

Vandalism and Resoration: The monument originally constructed at the Initial Point was a stone and concrete structure six feet high and eight feet in circumference at it's base, with a four foot circumference at the top. From the top of the stone monument, an 8 foot pole jutted higher into the sky, making the total height of the monument fourteen feet. I can't find any photos or information on when the original was destroyed, but it was long gone in 1984 when six agencies got together to refurbish the monument. (BLM Cadastral Survey Team, AZ State Lands Dept, Salt River Project, Gila River Indian Community, AZ Professional Land Surveyors Assn, and Bureau of Reclamation).

The 1984 refurbishment was not a replication of the original tall monument, but rather the flat concrete cross that exists today. In 2002, the monument was awarded status on the National Register of Historic Places. A plaque indicating it's historic status was erected near the monument and can be seen today. Additional refurbishment occurred in 2006.

Location and Access: Monument Hill is divided by the principal meridian, with the west side belonging to Phoenix International Raceway (PIR) in the City of Avondale, and the east side belonging to the Gila River Indian Community. While there are currently no signs posted prohibiting access--and a well traveled trail (the remnants of an old road) leads to the summit on Gila River Indian Community land--hiking and other kinds of recreation on Gila River land is subject to tribal laws and regulations. Please make sure you are in compliance before proceeding onto tribal lands.

The west side of the mountain is owned by PIR. Monument Hill is used for seating during race events. Access to this side of the hill is only permitted during race events with a valid ticket. During non-event days, access to the hill requires the permission of PIR, the owner of this private property! Please respect private property and obtain necessary permission to hike on any non-public lands!

Keep in mind that if there is an event at PIR, more than 75,000 fans may be in attendance, making traffic and parking an issue. You will very likely be unable to park anywhere near here without a ticket.

Hike: From the parking area, proceed through the gate into the B&M Wildlife Area. A gate in the fence along the walkway opens to the east. Proceed down along the base of Monument Hill following the old roadbed. Follow it as it turns southward and climbs the mountain. The monument and register are clearly marked at the peak. Head back the way you came, or follow the road south along the fence line toward the racetrack before turning back toward the parking lot.

Also Nearby: The Base & Meridian (B&M) Wildlife Area is a 200-acre BLM preserve at the confluence of the Salt and Gila Rivers managed by Arizona Game and Fish. This is a wetland riparian riverbank habitat and is open to recreation including fishing. There are excellent bird-watching opportunities with common species including: white-winged dove, mourning dove, gambel's quail, coots, Yuma clapper rails, western yellow-billed cuckoo, and gallinules. Other wildlife includes common yellowthroat, great blue heron, belted kingfisher, western screech-owl, beaver, bobcat, desert kangaroo rat, javelina, California kingsnake, Sonoran mud turtle, and western diamondback rattlesnake. Additionally, special status species including Lowland leopard frog, Ferruginous hawk, great egret, loggerhead shrike, osprey, American peregrine falcone, southwestern willow flycatcher, California leaf-nosed bat, and Sonoran desert tortoise occur on or near the B&M Wildlife Area. (Species reported via

Check out the Official Route and Triplogs.

Gate Policy: If a gate is closed upon arrival, leave it closed after you go through. If it is open, leave it open. Leaving a closed gate open may put cattle in danger. Closing an open gate may cut them off from water. Please be respectful, leave gates as found.

Leave No Trace and +Add a Triplog after your hike to support this local community.

2013-01-22 chumley
    WARNING! Hiking and outdoor related sports can be dangerous. Be responsible and prepare for the trip. Study the area you are entering and plan accordingly. Dress for the current and unexpected weather changes. Take plenty of water. Never go alone. Make an itinerary with your plan(s), route(s), destination(s) and expected return time. Give your itinerary to trusted family and/or friends.

    Most recent Triplog Reviews
    Monument Hill - B&M Wildlife Area
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    One of my favorite places to get in an easy run and it's only 5 minutes from my house. But to get one thing off my chest, what is it about people who fish? No matter where I have gone hiking or running, if the trailhead is shared with fishermen the area is always disgusting. Pulled into the parking lot of Tres Rios over by PIR. The first quarter mile was a filled with trash, beer cans, empty gas station bladder busters, pizza boxes and other assorted fast food wrappers. Go on the other side of PIR and the trailhead for the hiking loops over there might have a banana peel or two and maybe a empty gel packet if that.

    Started off the run and ran into nature's own swamp cooler. The temperature dropped about 10 degrees as soon as I crossed over the bridge by the parking area. There was a slight breeze coming off the water, almost made it feel chilly. Ran out to the top of the diversion dam and along the top of the dam for about 1.5 miles. Then came back by following one of the trails along the water back to the base of Monument Hill. Took a quick spin up to the top of Monument Hill then trotted back to my car.

    Saw lots of birds, a pack of javelina and snuck up on a coyote. Was able to get within 10 yards of the coyote before he noticed me.
    Monument Hill - B&M Wildlife Area
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    Doing a twofer today. Girlfriend wanted to get out of the house to stretch her legs and I convinced her to try Monument Hill as it's only 5 minutes from our house. Probably the most garbage strewn hike in the area, only to get worse when NASCAR comes to town in two weeks.

    Great views of the area and we found a horseshoe on the trail. One of the hidden gems of the westside.
    Monument Hill - B&M Wildlife Area
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    Another day for a leisurely run. Parked at the base of Monument Hill and ran north towards the diversion dam. Scrambled to the top of the dam and ran along the dam ended. Then worked my way back on the dirt roads just south of the dam until I got back to Monument Hill. Finished the run with a quick ascent up Monument Hill.

    Only downside to the run is how much trash is still left over from the NASCAR race last month. Luckily the fans can't waddle that far and most of the trash is confined to the first third of a mile from the parking area.
    Monument Hill - B&M Wildlife Area
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    Made my way through all the accessible marsh areas. There was plenty of water and tons of birds, but my P/S camera does not zoom well, I need a real birding set up (300-400mm lens :))

    I was the only car there at sunrise, which is a nice change. The scurvy types, boozers and people who leave garbage were not around. What a shame.....these uneducated/ignorant people can really trash a beautiful area.

    The city could spend hundreds of man hours, just picking up garbage, it really irritates me :SB: - that our citizens are that stupid and inconsiderate, or just plain ignorant :gun: :gun: And the poor birds, its ironic that the best habitats are in scum-ball areas, like the Gila, Rio Salado, Salt River basin. These morons need to realize, just how fortunate they are :bdh: Ok.......I get it! the end!
    Monument Hill - B&M Wildlife Area
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    On our way to Rainbow Valley, I decided that I had to experience where it all began, and made my way to Arizona's Initial Point. After bagging a small peak next to Estrella Mountain Park and realizing I probably should have looked at the map a little bit more closely, we drove back east a couple of miles and bagged the correct peak! Simple hike, surprisingly many people in the B&M Wildlife area enjoying the beautiful weather and sunset. Sure wouldn't want to be here on a race day. Only one other person up on the hill though.

    I had read that you need permission from PIR to hike the hill, but the track was open and plenty of people were milling about and didn't seem to care at all about us being on the hill. Despite knowing the boundary of the Reservation, I didn't see any signs, barricades, or other obvious markers indicating that meandering a few yards onto Res land was in any way discouraged. But that was my experience. Proceed at your own risk.

    It was cool to see the monument. It's a must-visit site for any other nerdy people like me who like benchmarks and such.

    Permit $$
    information is in description

    Map Drive
    Paved - Car Okay

    To hike
    Drive to west Phoenix on I-10 and exit on Avondale Blvd/115th Ave. Drive south 6 miles and turn left into the PIR parking lot after crossing the Gila River bridge. Follow the road 1/2 mile back toward the river and park in the marked stalls or dirt lot at the end of the road.
    page created by chumley on Jan 22 2013 12:17 pm
    $17 3L Hydration Bladder
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