An absorbent core (101, 501, 601) comprising: a front portion; a back portion; a middle portion positioned between the front portion and the back portion; and a longitudinal axis extending along a length of said core (101, 501, 601) and crossing said front, middle and back portions (122, 126, 124), the absorbent core (101, 501, 601) having a width extending perpendicular to said length and a perimeter comprising at least two opposing ends (102, 103) and at least two opposing sides (104, 105) positioned between said ends (102, 103), said core (101, 501, 601) being a multi-layer core comprising at least two distinct core layers (502, 503, 602, 603), wherein a first core layer (502, 602) comprises a first concentration of super absorbent polymer (504, 604) therein and a second core layer (503, 603) comprises a second concentration of super absorbent polymer (504, 604) therein said first and second concentrations being different and wherein the second concentration of super absorbent polymer (504, 604) is greater than the first concentration of super absorbent polymer (504, 604), and wherein at least said first core layer (502, 602) comprises one or more channels, said channel(s) being continuous and interconnected at least along the length and the width of said core (101, 501, 601) such that at least two channel portions (107,108) extending along said length are in fluid communication via a connecting channel portion positioned proximal to said back portion, wherein said connecting channel portion forms a substantially U-shaped bend, and wherein the first core layer (502, 602) comprises at least one core wrap substrate (505, 506, 605, 606) enclosing the superabsorbent polymer therebetween and wherein a top layer (505, 605) of the core wrap is adhered to a bottom layer (506, 606) of the core wrap in regions of said core comprising the channel(s), and wherein said concentration refers to the amount of said superabsorbent material divided by the surface area of said layer over or within which the superabsorbent material is contained. a front portion; a back portion; a middle portion positioned between the front portion and the back portion; and a longitudinal axis extending along a length of said core (101, 501, 601) and crossing said front, middle and back portions (122, 126, 124), the absorbent core (101, 501, 601) having a width extending perpendicular to said length and a perimeter comprising at least two opposing ends (102, 103) and at least two opposing sides (104, 105) positioned between said ends (102, 103), said core (101, 501, 601) being a multi-layer core comprising at least two distinct core layers (502, 503, 602, 603), wherein a first core layer (502, 602) comprises a first concentration of super absorbent polymer (504, 604) therein and a second core layer (503, 603) comprises a second concentration of super absorbent polymer (504, 604) therein said first and second concentrations being different and wherein the second concentration of super absorbent polymer (504, 604) is greater than the first concentration of super absorbent polymer (504, 604), and wherein at least said first core layer (502, 602) comprises one or more channels, said channel(s) being continuous and interconnected at least along the length and the width of said core (101, 501, 601) such that at least two channel portions (107,108) extending along said length are in fluid communication via a connecting channel portion positioned proximal to said back portion, wherein said connecting channel portion forms a substantially U-shaped bend, and wherein the first core layer (502, 602) comprises at least one core wrap substrate (505, 506, 605, 606) enclosing the superabsorbent polymer therebetween and wherein a top layer (505, 605) of the core wrap is adhered to a bottom layer (506, 606) of the core wrap in regions of said core comprising the channel(s), and wherein said concentration refers to the amount of said superabsorbent material divided by the surface area of said layer over or within which the superabsorbent material is contained.