The 3rd Corps, 1st Division, 2nd Brigade was also known as Ward’s Brigade. During the battle of Gettysburg, it served as a member of Birney’s Division in the Third Corps, Army of the Potomac. The brigade was commanded by Colonel J John Henry Hobart Ward (June 17, 1823 – July 24, 1903), a career United States Army soldier who fought in the Mexican–American War and served in the New York state militia. During the Civil War he was wounded several times, and noted for both his performance in the 1863 Battle of Gettysburg and for his misconduct in the 1864 Battle of the Wilderness. After the war Ward worked in New York's Superior Court, and was also remembered for his death when he was hit by a train. Ward lost 781 officers and men out of 2,188 present, a loss of 35.7%. Ward suffered a wound on July 2 but did not relinquish command.
The Ward's Brigade tablet can be found on Sickles Road, on the right or east side of the road if traveling north, at the most southern point of Rose Woods, right where it begins, at the corner. This area is the above and north of Devil's Den even many call it the Devil's Den area; it is not. This is however Houck's Ridge and the trees from Rose Woods make aline there going north along the ridge. This is where in the mid-afternoon of July 2, 1863, the 4th Maine was deployed in the low area there, below the tablet. As a reference the 
124th New York Monument is 126 feet south of this position which means you would have to pass this monument also on the right if traveling north. 
Safe parking can be found 300 feet to the rear or south of this position at the enlarged should area at the top of Devils Den. I parked at the tablet which one can do provided you are careful and allow room for others to pass. Take care to not park on anything remotely green looking as Park Police will happily ticket you. I visited this site on Monday, July 1, 2013 on the 150th anniversary of the Battle of Gettysburg @ 4:53 PM, EDT & @ an altitude of 542 feet, ASL. As always, I used my trusty and oft abused Canon PowerShot 14.1 Megapixel, SX210 IS digital camera for the photos.
The monument work was completed under the direction of the Gettysburg National Park Commission (established by the United States Department of War), after they took over the administration of the park from the Gettysburg Battlefield Memorial Association (whose funds had expired) on March 3, 1893, and whose stewardship was then transferred to the National Park Service in 1933) SOURCE. According to the NRHP narrative, this monument was built in 1911 but finished in 1912, which according to my experience is questionable. I can't resolve if the 1912 date represents a completion of the physical construction of the tablet or an installation date. Other sources have it at 1910 & 1912. Another source wrote the last of the Confederate Brigade tablets was completed in December 1910. I don't know if anyone actually kept exact records of when these things were installed.
These battery tablets were cast by Calvin Gilbert. Gilbert joined the 87th Pennsylvania Volunteers when the "Rebellion" broke out. Since he was musically inclined, he was made a member of the regimental band. In early 1863, he was promoted to the rank of Captain and sent to Washington D.C. for commissary duty. He served in that capacity until the war ended in 1865, and at war’s end earned the brevet rank of Major. 
After returning home to Gettysburg, Major Gilbert moved his family to the town of Chambersburg, where he served as the Superintendent of Schools. He also opened an iron foundry there in 1868. When Calvin learned, nearly thirty years later, in 1894, that the Gettysburg Foundry was available, he purchased it with a business partner & moved his family back to Gettysburg. For the next twenty years, the Calvin Gilbert Foundry created ironworks that are still seen today on many historic forts and national battlefields (this tablet), from upstate New York to Florida to Lookout Mountain. Gilbert lived to be 100 years old and attended the Last Reunion of the Blue and Gray for the 75th anniversary of the Battle of Gettysburg when he was 99. He was a most remarkable man and lived an amazing life.
There is an excellent excerpt in the American Guide Series about Gilbert attending the 75th reunion anniversary.
Look carefully on the reverse side of one of these tablets and his name might be there; I found a tablet or two like this. This one of course is devoid of his name. The inscription on the monument reads:
Army of the Potomac
Third Corps First Division
Second Brigade
Brig. Gen. J. H. Hobart Ward
Col. Hiram Berdan
20th Indiana, 3d. 4th. Maine
86th. 124th. New York, 99th Penna Infantry
1st, 2d, (8 cos.) U.S. SharpshootersJuly 1 Arrived after sunset and bivouacked for the night.
July 2 The Corps having relieved Second Division Twelfth Corps in the morning the Brigade took position on the left of the Division and extended to the base of Little Round Top. Between 2 and 3 p.m. advanced with the Division to the line from the Peach Orchard to Devil's Den occupying the left of the line to the west base of Little Round Top. The 1st U.S. Sharpshooters and 3d Maine were engaged in a reconnoissance into the woods in front of the Peach Orchard from noon until about 2 p.m. and then served with First Brigade at the Peach Orchard. The 6th New Jersey and 40th New York were sent to Brig. Gen. Ward and supported his left. Between 4 and 5 p.m. the Brigade was fiercely attacked by Brig. Gen. Robertson's and Brig. Gen. Benning's Brigades supported on their flanks by Brig. Gen. Law's and Brig. Gen. Anderson's Brigades, Major Gen. Hood's Division and after a prolonged conflict was forced back.
July 3 In reserve.
Casualties. Killed 12 Officers 117 Men. Wounded 33 Officers 449 Men. Captured or missing 8 Officers 164 Men. Total 781.
There are hundreds of non-sculpted monumentation for the various Confederate States & Union units which fought at Gettysburg. There are about 10 different variations of tablets, markers and monoliths by my reckoning. Six designs represent brigade (2), division (2), corps (2), & army headquarters (2), each different in a subtle way so as to distinguish between armies. Battalion/ battery / advance position markers and regimental monuments for United States Regulars & Confederate have their own distinct design (2), bringing the total to ten designs at the battlefield. The bronze tablets (the brigade monuments) were created by Albert Russell & Sons Co. of Newburyport, Massachusetts. The granite bases which accompany the various tablets were created by the Van Amringe Company out of Boston, Massachusetts. The cast iron tablets were of course manufactured by the aforementioned Calvin Gilbert. The 1910 Gettysburg Commission report lists the awarded contracts to these companies (not Gilbert) for the tablets.
All of these tablets were designed by architect Colonel Emmor Bradley Cope (July 23, 1834 - May 28, 1927). He designed pretty much every tablet for both the Union and Confederate armies, each one distinct, with several different varieties. He is buried in Evergreen Cemetery in Gettysburg, as well he should be as this park and most of the things seen here today were designed by him and as such, are his legacy.
These monuments/tablets were erected just after the turn of the century during the first and beginning of the second decade of the 20th century. Each one has since been preserved or restored at least twice since the turn of the 21st century. The plaques and tablets were erected by the Gettysburg Park Commission (established by the War Department). The Gettysburg Park Commission is also referred to as the Gettysburg National Military Park Commission or the Gettysburg National Park Commission, to clear up any confusions, especially my own.
On October 1, 1898, the Gettysburg National Park Commission in a letter to the Secretary of War set gave recommendations for continuing the task of organizing and progressing the work of the Gettysburg National Military Park. Every November they wrote their annual report which outlined the work of the GNPC for that year. The following is an excerpt from that report relevant to this waymark. The link at the end of the paragraph will take you to the entire report. The method of marking the positions of troops on this field, as approved by the War Department, is to place the principal tablet or monument of each command at the position occupied by the command in the main line of battle, and to mark the several important positions subsequently reached by each command in the course of the battle by subordinate and ancillary tablets, with appropriate brief inscriptions giving interesting details and occurrences and noting the day and hour as nearly as possible. SOURCE
Most of the Commission reports have been digitized and can be found HERE. The initial 1893 report up to and including 1921 can be found here. 1922 to 1926 are missing and have yet to be discovered. The years 1927 to 1933 were discovered in 1996 and are also included. To my knowledge this is the most comprehensive list of documents that illustrated the development and formation of the park.
Information about these specific types of monuments:
BRIGADE HEADQUARTERS MARKERS (FOR UNION & CONFEDERATE TABLETS)
The Brigade Headquarters (and Confederate artillery battalions, equivalent to Union artillery brigades) are bronze tablets mounted at an angle on a stone pedestal and describe the movements and itinerary of each memorialized unit. Union headquarters have rounded tops and square bases. Confederate headquarters have flat tops and round bases. Union headquarters are marked with their corps or service branch symbol (like a cross, clover or crescent moon), while Confederate headquarters are simply labeled "C.S.A.". There are seventy-four brigade markers at Gettysburg honoring the Union's various brigades. (Other sources say there are seventy-five). There are sixty-four brigade markers honoring the Army of North Virginia's various brigades. The Union Brigade tablets consist of sea-green granite with a square 36” x 36” base; they weigh 3500 pounds. On each pedestal is mounted a bronze tablet with rounded corners weighing 300 pounds. They were built by Albert Russell & Sons Co. of Newburyport, Massachusetts and Charles Kappes. The Confederate Brigade tablets consist of red circular Maine granite bases 34 1/2 inches diameter and weighing 3,000 pounds. On each base is mounted a 300 pound bronze tablet. They were built by Van Amringe Granite Company (pedestals), Albert Russell & Sons Co., Newburyport, Mass (tablets) and Charles Kappes (foundations). SOURCE & SOURCE
The Ward's Brigade - US Brigade Tablet is a contributing feature to the Gettysburg Nat'l Military Park H.D. which is nationally significant under NR Criteria A, B, C & D. Areas of Significance: Military, Politics/Gov't, Landscape Architecture, Conservation, Archeology-Historic. Period of Significance: 1863-1938. The monument is designated as structure no. MN481.
From the Nomination Form:
1 of 75 Civil War US Brigade Tablets in Park. Records movement & itinerary of Ward's Brigade during Battle of Gettysburg, July 1-3, 1863.
Short Physical Description:
onze inscription tablet, 4”0’ x 3’8”, attached to slant face of polished sea green granite monolith. 3’0” squared base of monument tapers to a smaller dimension at the tablet. All 5’4” H.
Long Physical Description:
Located on S portion of Sickles Avenue, above Devil's Den.
Source
1. NRHP Nomination Form
2. Stone Sentinels