Not the ark of the covenant
With the rich history, mythical, mystical and real, and with the prominent place Aksum, even now, holds for Ethiopian Christians, the town and it's sights are a major letdown. The invisible centerpiece is the Ark of the Covenant, supposedly the actual container built to house the tablets with the ten commandments, given by god to Moses.
Tradition holds that the queen of Sheba, of whose existence there is no contemporary historical evidence, visited King Solomon in Jerusalem, was more or less tricked in having sex with him and ended up returning pregnant, mothering the future king Menelik, who then went back to claim the Ark as his own, supposedly returning with a thousand Jews of each of the tribes, 12000 Total.
All Ethiopian kings since have claimed direct lineage from Solomon and it is why, for example, the last emperor of Ethiopia, Heile Salasie, was called the lion of Judah.
But, also, Ethiopians were amongst the first to adopt Christianity as a state religion, together with Armenia and Georgia and, because of these early victories over the Roman empire, the country has St. George as its patron saint, just like Georgia, Egypt and England, to name a few.
In popular culture, the ark residing in Aksum only became common knowledge in the 17th century and is now housed in a small, rather boring, chapel close to the center of town. On one side, there is a nice 16th century church, perhaps on the site of the first church in Africa and off limits to women, on the other side, there's an imposing, not exactly getting it right, church built under Heile Selasie's patronage, while roughly under this modern church, in a museum, there's an impressive collection of crowns and crosses, very badly displayed.
Sadly, the whole thing is very underwhelming, not in the least because the chapel with the ark is completely off limits, only one person having access to the chapel itself, but also because the churches and museum are simply not very interesting, or at least poor cousins of their cousins the world over.
And the trick that, after paying a sizable amount for entering the grounds, a caretaker has to open up the churches for you, which really are closed, stays close, and then expects, however timidly, a compensation for his efforts, is a bit annoying. Granted, our 'guide' was friendly and helpful, but the setup is still a ploy.
Other sights include mildly interesting collections of stelae, a few ruins and a few tombs.
Little remains of the early Aksumite kingdom. Whether once ruled by Sheba or not, wealthy it once was, spanning both sides of the red sea. The founders, Sabaen, were once thought to be Arab, though recent evidence suggests it more likely that there was at least a significant local, African, component to it as well. Also, it has been shown that the Sabaens, one of the three 'people of the book' as mentioned in the Quran, were in fact likely Manacheans, followers of Mani, a third century prophet whose amalgamation of religions once had followers from Carthage to China, while the faith died out after the arrival of Muhammad.
Still, it is then no surprise that Ethiopia's form of Christianity is an obvious mix of Jewish and Christian faiths, with perhaps a sprinkling of Zoroastrianism, Mani's third ingredient to his religious mix.
Within striking distance, the rock churches of Tigray, semi-monolithic as opposed to Lalibela's monolithic churches, are said to be a worthy visit, but are also difficult to get to, and can require a lot of hassle with their religious caretakers. If they haven't gone off to market, collectively.
Also nearby is the site of the biggest African defeat of a colonial power. Menelik II curbed the Italians' intentions in 1896, defeating them at the battle of Adwa. Important to Ethiopia, little remains at the battle site.
Perhaps most fun was had on the terrace of the Yeha hotel. Staff crumble up uneaten bread which is then fought over by hornbills, squirrels and hawks, which also try to score the squirrels.