When you go into the Museum Gardens through the main gate on Museum Street, and turn right as soon as you enter, this is what you see. Wander a little further down, and you see there are tombs inside this tunnel, and the ceiling is a Norman vaulted one.
This section of the ruins in the gardens is actually part of the remains of St Leonard's Chapel and Hospital, a place where the sick and poor came to be healed - in spirit as well as body, and was apparently the largest such place in the north of England. It was rebuilt after a fire in 1137, which is when these ruins date from.
Not pictured here (I'll post a photo when I have one!) is a spacious undercroft, off to the left from the tunnel, which has some beautiful arches. I was actually too scared to go down there and get pics the other day when I took these as it was getting dark! It was the prospect of meeting one of the dodgy types that sometimes hang around here that put me off though, more than the prospect of ghosts. Although I admit, that did also cross my mind. Eek!
This part above definitely does spook me a bit. It's the inside of the "tunnel" and the graves are Roman ones. I seem to remember reading that they weren't found on site, but have been found at excavations in other parts of York.
Funny how just across to the right beyond the park's railings is one of the busiest roads in York, with bus stops, people and loads of traffic. Then along at the end of this tunnel, which you can just see, is the forecourt to the library with people constantly coming and going. I can't help feeling in a totally different world just here though, and civilisation seems far away.