One of the biggest promises that Donald J. Trump made to Americans during his campaign for the presidency was a wall that would run almost 2000 miles across the United States’ shared border with Mexico. Now, almost a year after his election, he is attempting to make that promise a reality.

There have been a few ideas thrown around, including one for a wall with solar panel attachments. That idea has since proven implausible and will not be in the running for the final design of the border wall. Six contractors from across the country have been hired to build eight prototypes, and when completed, these prototypes will be tested by the Department of Homeland Security.

There are many steps that still must be taken before the wall can become a reality. Most of the land that would hypothetically be used is currently privately owned land in Texas, and that land will have to be seized. Homeland security attempted to build a wall in the Rio Grande Valley in 2008, and over 300 cases regarding the seizure of private land by the government made their way into court. Most are still pending.

There is also the matter of funding. The Senate has yet to approve the funds to build this costly wall. Money from other programs was used by the Homeland Security Council to build prototypes. The House Homeland Security Committee voted to approve the funds for the prototypes, but Senate Democrats have vowed to block it before the wall could be built in its entirety.

Up to $500,000 per prototype was allotted, and estimates for building the entire wall have reached numbers up to 38 billion.