One county in northern Virginia holds more than 300 data centres and is routinely said to carry around 70 percent of the world's internet traffic. The local utility now has more requests for power than it can connect, and the queue is measured in years.

You have almost certainly never heard of Loudoun County, Virginia. It sits roughly forty kilometres west of Washington DC, covers about 520 square miles, and holds about 450,000 residents, which is fewer people than live in the Newcastle-Gateshead metropolitan area in the north of England. The place is not on any tourist itinerary, and it isn’t famous for anything the way a wine region or a beach town is famous. Yet there is a reasonable chance that when you last opened Instagram, checked your bank balance, or asked an AI assistant anything at all, the packet of data doing the work touched a warehouse full of servers in Loudoun before it came back to your phone.

The specific number the county’s own economic development team likes to quote is that around 70 percent of the world’s internet traffic passes through it, though the county government itself uses a softer version of the same claim on its official materials, saying that much of the world’s internet traffic flows through Loudoun’s digital infrastructure. The exact figure has been argued about for years. What is not argued about is that Loudoun holds the largest concentration of data centres anywhere in the world by a significant margin, and that everyone in the industry, from Amazon to the Pentagon, treats Ashburn, its small unincorporated town at the eastern end, as the capital of the physical internet.

How it got there

The story begins in 1992, when engineers from Metropolitan Fiber Systems and UUNet ran a set of cables together in a parking garage in nearby Vienna, Virginia, creating one of the first commercial internet exchange points on Earth. That exchange, known as MAE East, was the physical location at which competing internet service providers agreed to pass one another’s traffic to each other. It made the neighbouring flat land in Loudoun the most attractive real estate in the world for anyone who wanted their servers to reach the rest of the internet in as few milliseconds as possible. When America Online opened its headquarters in Ashburn in 1996, and UUNet followed two years later, the pattern was set.

In 2000, the county’s zoning administrator decided, for administrative simplicity, that data centres should be regulated like ordinary office buildings, which meant that developers could build them by right in vast swathes of the county without any additional legislative approval. According to the Loudoun County government’s own official history of the industry, that single administrative determination, made in a suburban zoning office, produced the largest data centre cluster on Earth over the following twenty-five years.

If you want the bigger picture behind that queue, the video below has it — the pledges made before the AI boom, what’s actually happened to the emissions since, and why the companies most committed to fixing this are the ones driving the demand.

The current scale

As of March 2026, there are approximately 233 data centre buildings in Loudoun, holding roughly 56.5 million square feet of server floor space either built or under construction, with the average new building now closer to 340,000 square feet. A further 35.7 million square feet is approved but not yet built, and another 20.7 million square feet is in the legislative pipeline waiting for approval. Data centre-related tax revenue reached $1.2 billion in fiscal year 2026, which is 39 percent of the entire county budget. The projection for 2027 is $1.3 billion, at 40 percent. In a jurisdiction that used to depend on residential property taxes, roughly two out of every five dollars the county spends now come from server warehouses.

The utility problem

The utility that serves this cluster is Dominion Energy Virginia, and its 2025 annual report to the Securities and Exchange Commission makes for genuinely startling reading. According to Dominion’s own SEC-filed 2025 annual report, data centres already accounted for 28 percent of the total electricity Dominion Energy Virginia sold in 2025, up from 26 percent the year before. Peak load in the region is projected to grow by 5.4 percent per year over the next decade, and 38 of the top 50 all-time peak demand records for the region were set in 2025 alone, with the 22 highest all belonging to that single calendar year. The company is carrying more than 48 gigawatts of additional data centre capacity in various stages of contracting, a figure roughly equal to the entire electricity consumption of the United Kingdom on a summer afternoon.

The queue for new connections is now measured in years. Independent industry reporting has documented cases where delivery timelines for facilities above 100 megawatts have stretched from three or four years to as long as seventeen, and in response some data centre operators have begun building their own onsite gas turbines and running diesel backup generators for days at a stretch when the grid falters.

The response

The pushback has arrived on multiple fronts. In 2025, Loudoun County eliminated the by-right development pathway for data centres, requiring future proposals to go through a special exception process with a public hearing and a Board of Supervisors vote. Dominion, at the state utility commission’s direction, will begin requiring high-load customers from January 2027 to sign fourteen-year commitments to pay for the power they have asked for even if they use less, as a way of stopping speculative applications from clogging the queue. Multiple bills before the Virginia General Assembly have attempted to give local governments legal authority to deny data centre applications where the grid cannot support them.

What this actually is

The internet has always been physical: the cloud is a warehouse, and the AI everyone is talking about is a rack of processors that draws as much power as a small town. What is different about Loudoun is not that the physical layer exists there but that so much of it exists in one place, having outgrown the electrical infrastructure of the actual county it sits in, being asked to accommodate an artificial intelligence boom that on current forecasts will double its power demand again by 2030. The queue for new connections is measured in years because the grid it was built to serve was designed for something else entirely.