Project Overview: MagnumStone Revamps Infrastructure at Historic American Site

In 2023, Little Round Top in historic Gettysburg National Military Park underwent major upgrades to improve visitor safety and accessibility. A new retaining wall was required at the summit’s parking area to raise the slope’s grade and streamline traffic flows. To achieve the project’s timelines, long-term strength and aesthetics, MagnumStone’s gravity wall system and extenders delivered a resilient, versatile solution.

As part of the site’s extensive rehabilitation project, the MagnumStone retaining wall helped revamp critical parking lot infrastructure. Trails, monuments and other aspects of the national park were also refurbished to restabilize eroded soils and promote re-vegetation. The summit’s new retaining wall supports safe, accessible gathering areas and sidewalks that accommodate large volumes of tourists.

This project was proudly selected as the winner and top project in
Hardscape North America’s 2025 ‘Retaining Walls – Commercial’ category.

Project Challenges & Solutions: Secure Reinforcement, Versatile Wall Design

Originally specified as a geogrid-reinforced granite boulder wall in an ashlar pattern, the design posed significant procurement challenges. During the early stages of construction, general contractor Structural Engineering Group (SEG) proposed MagnumStone as a value-engineered soil retention solution.

Significant factors that MagnumStone helped this project address:

• MagnumStone blocks were more affordable and readily available
• Gravity wall design with extender units minimized difficult excavation
• Block facings were stained to blend into Gettysburg’s natural landscape
• Secure wall design & fence built directly into blocks increase visitor safety

Approved by the National Park Service, MagnumStone’s hollow core concrete blocks were supplied through York Building Products. The gravity wall system presented cost savings, and enhanced performance to meet the unique needs of this high-profile project. Customizations were made to maintain the original design’s granite ashlar pattern along the parapet wall design facing the parking area. This was accomplished by installing veneer along the back of the MagnumStone retaining wall’s highest courses.

Excavation was complicated by rocky terrain atop the storied Battle of Gettysburg hillside. The interlocking gravity wall design and MagnumStone’s gravity extender units greatly minimized excavation depths compared to alternative solutions. This ensured that more of the surrounding historic site remained preserved and expedited the retaining wall’s installation costs and time.

Wall Design: MagnumStone Hybrid Gravity & Parapet Design Solution

This retaining wall features a unique gravity retaining wall design, the top courses serving as a parapet finishing detail. At its highest point the wall reaches a 10 ft. (3 m.). It supports active pressures from the roadway, plus a new sidewalk and gathering areas for loading and unloading tour buses.

MagnumStone’s wall design advantages for this historical site included:

• Gravity extender units provide secure, space-efficient wall reinforcement
• Standard blocks cover 8 sq. ft. (0.74 sq. m.), reducing block quantities
• Versatility to build a hybrid gravity and parapet retaining wall design
• Built-in lateral and vertical drainage channels for superior drainage
• MagnumStone’s durable precast concrete blocks last generations

ELA Group, the project engineer, designed the gravity wall using MagnumStone’s 2 ft. and 4 ft. gravity extender units to amplify wall mass. Located alongside a narrow, sloped roadway, the gravity wall easily navigated continuous elevation changes and follows the terrain’s natural grade.

Its two upper courses were formed and filled with concrete to support a double-sided appearance and safety fencing. The fence posts were installed directly into the blocks’ hollow cores for a simple, elegant finishing feature atop the wall.

Installation: Benefits of Hollow Core Blocks & Gravity Extender Units

The gravity wall approach streamlined this project for the team at SEG who installed the retaining wall. MagnumStone’s hollow core units, weighing roughly 1,400 lb (635 kg) were easily handled and placed with compact construction equipment. Using smaller equipment and stacking block inventory on-site, eliminating the need for large staging areas. This was critical when working in a constrained space, and important to preserving the historic area.

MagnumStone’s gravity wall and extenders eliminated the need for extensive excavation that’s required for geogrid reinforced retaining wall designs. This saved valuable time and labor costs, while minimizing project delays. Drainage gravel filled the blocks’ hollow cores to improve drainage, further enhancing the wall’s long-term strength and durability.

To achieve the parapet feature atop the wall, the top courses were filled with concrete for key design purposes. The concrete securely filled the interlocking notch for gravity extenders, making a smooth surface behind the upper blocks. This made it easier to attach veneer to the public-facing side of the block. It also securely holds the fence posts in place.

Block Aesthetics: A Creative Approach to Parapet Retaining Wall Finishes

Maintaining the natural appearance of the landscape was a vital aspect of this project. MagnumStone’s ledge face texture was chosen to echo the historic granite stonework typical of the region. After installation, the blocks were stained to better match the site’s natural granite color palette and blend into its surroundings.

On the visible parking lot side, the parapet’s concrete face was clad in granite-colored stone veneer. Cap units provided a polished finish that reinforce the site’s historic tone. The parapet wall designates a new gathering area for tour buses, making a beautiful first impression for many visitor experiences.

Project Summary: MagnumStone’s Modern Wall Design a Victory for Gettysburg

The Little Round Top retaining wall demonstrates MagnumStone’s wall design and reinforcement adaptability in constrained space for historically sensitive infrastructure. MagnumStone’s precast system preserved the character of Gettysburg’s most visited battleground while reducing excavation and saving significant time and costs.

• MagnumStone delivered a hybrid gravity and parapet retaining wall design
• Gravity extenders added mass and minimal wall depth to reduce excavation
• Versatility to install a fence directly in top courses, attach veneer to back of blocks

With its massive block size, adaptable design features, and ruggedly natural appearance, MagnumStone proved to be the ideal solution for this iconic site’s modern accessibility upgrades. The resilient engineered stability of this gravity wall will improve visitors’ safety and accessibility to Little Round Top for generations.

Why Choose MagnumStone

Retaining wall design versatility like MagnumStone’s is a valuable asset for engineers, architects and contractors to build creative, customized features. With multiple reinforcement designs including gravity extenders, geogrid and cantilever or soil nailing for extreme applications, the system offers exceptional flexibility. Projects with difficult access, minimal excavation area and limited staging areas can be simpler to plan and build with MagnumStone.

Learn more about MagnumStone’s robust wall design solutions by downloading its free, comprehensive Retaining Wall Design & Analysis Software. This software saves time during the planning and design phases, while the hollow core precast system expedites on-site project installations. Keep project on time and on track with MagnumStone retaining walls.

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This project was successfully completed thanks to York Building Products (MagnumStone block producer), Structural Engineering Group (Contractor) and ELA Group (Engineer).