Where is it?
M50 junction 3, the point where the M50, an inconsequential motorway carrying very little traffic comes across an even less important B-road, and for no apparent reason interchanges with it.
What's wrong with it?
Quite aside from the fact that there's really no need for it to be there, it's shockingly below standard for a motorway. There are no sliproads or deceleration lanes to speak of, simply very very tight bends which end abruptly a few feet from the motorway at Give Way signs. There isn't even any traffic island between the entry and exit points — just a painted triangle on the carriageway. And to verify that this junction truly is abysmal, the signs on the M50 in advance of the junction aren't the normal fork ones but instead show the exit leaving at 90 degrees from the motorway — which it does!
Why is it wrong?
The M50 is in the top 5 of earliest motorways to open, though it's a complete mystery why as even today it's barely used. There's even less reason, then, for a junction with the B4221, and so it's quite fitting that the junction that is there is barely more than a gap in the motorway's boundary fence. Experimental 1960s design standards — similar to some of the junctions on the M2 before the recent upgrades — are largely to blame here.
What would be better?
Just close it off — there's no need for a junction anyway! This wouldn't take much effort at all, just wipe off the exit markings, draw a hard shoulder line across and grass over the space between the motorway and the B4221.
Right to reply
Growing up in Gloucester in the 70s, an upgrade to the B4215/B4221 to the M50 was mooted as a replacement for the very twisty A40 between Gloucester and Ross. Had that happened, it would no doubt have had to include an upgrade to that junction. We used to use it when going on family holidays to Pembrokeshire and it certainly felt strange using a T-junction to join the motorway!