The M61 connects Manchester to Preston and points north by taking a direct line from the M60 Manchester Outer Ring Road to the M6. Without it, the junction between the M6 and M62 would be very busy and the A6 at Chorley would be something of a headache.
Its southern terminus and starting point, the Worsley Braided Interchange on the M60, is a contender for the most fabulously over-designed junction in the country. It occupies the first three junction numbers on the M61 and is considered the widest section of road in the UK, with seventeen lanes side-by-side across several carriageways. It is effectively two motorways running together, with sliproads linking them, and connecting routes to parallel and adjacent roads. Because skew bridges were difficult and expensive to build when it was created, some of the sliproads cross each other at very oblique angles using galleries - effectively long lengths of artificial tunnel.
It seems obvious to everyone who uses it that the M61 ends on the M60, and indeed the exit list below shows that happening - but that's really just a convenience based on the fact that it's the way most of the traffic goes. Officially, the M61 heads away to the south at junction 2, terminating on the A580, and journeys between the M60 and M61 take in a short section of connecting road.
After leaving the Worsley Braided Interchange, the M61 seems to have used up all its excitement quota and becomes quite remarkably dull. The landscape is hilly and quite industrial, and the road itself always seems to look very old and worn out. At Preston, the northern terminus on the M6 is very simple, which can be something of a disappointment after the excitement of Worsley.
The missing junction 7 is something of a mystery. Considering that an extended M58 was meant to terminate on the M61, and an underpass even exists to enable that to happen, the missing junction has nothing to do with that plan and is much too far north to be related to the long-dead M58 proposals. Instead, it was probably intended for an improved access to Chorley and the new town of Leyland.