Multilayer rotomoulded articles comprising: a) an external skin layer a) is a blend, preferably a dry blend or compounded blend of: i) from 20 to 99.9 wt%, based on the weight of external skin layer composition a), of a first polyethylene composition comprising from 40 to 99.9 wt%, based on the weight of composition i), of a first metallocene-prepared homo- or co-polymer of ethylene, from 0.1 to 60 wt% of ionomer and grafted polyolefin and from 0 to 60 wt% of functionalised polyolefin, or polyolefin grafted to non-polyolefin in the form of a block copolymer g-NPO), or a mixture thereof; ii) from 0 to 79.9 wt%, based on the weight of external skin layer composition a) of a second metallocene-prepared homo- or co-polymer of ethylene having different density and/or melt index than the first metallocene-prepared homo- or co-polymer of ethylene; b) an intermediate foamed polyethylene layer b) prepared from: i) 95 to 99.8 wt% based on the weight of foamed layer b) of a polyethylene composition, the same as or different from that of external skin layer a), said composition comprising a mixture of ionomer and grafted polyolefin, and ii) from 0.2 to 5 wt% of chemical blowing agent, and wherein the mixture of ionomer and grafted polyolefin, blowing agent and metallocene-prepared polyethylene resin have a synergistic effect; c) a internal skin layer c), that is a polyethylene-based layer, prepared from a composition consisting of - from 40 to 100 wt%, based on the weight of skin layer c) of a metallocene-prepared homo- or co-polymer of ethylene or a mixture thereof, based on the weight of skin layer b) composition, said polyethylene being the same as or different from that of external skin layer a); - from 0 to 60 wt% of a functionalised polyolefin or of an ionomer or of a polyolefin grafted to a non-polyolefin in the form of a block copolymer g-, or of a mixture thereof; d) optional layers further wherein the multilayer rotomoulded articles are boats. a) an external skin layer a) is a blend, preferably a dry blend or compounded blend of: i) from 20 to 99.9 wt%, based on the weight of external skin layer composition a), of a first polyethylene composition comprising from 40 to 99.9 wt%, based on the weight of composition i), of a first metallocene-prepared homo- or co-polymer of ethylene, from 0.1 to 60 wt% of ionomer and grafted polyolefin and from 0 to 60 wt% of functionalised polyolefin, or polyolefin grafted to non-polyolefin in the form of a block copolymer g-NPO), or a mixture thereof; ii) from 0 to 79.9 wt%, based on the weight of external skin layer composition a) of a second metallocene-prepared homo- or co-polymer of ethylene having different density and/or melt index than the first metallocene-prepared homo- or co-polymer of ethylene; i) from 20 to 99.9 wt%, based on the weight of external skin layer composition a), of a first polyethylene composition comprising from 40 to 99.9 wt%, based on the weight of composition i), of a first metallocene-prepared homo- or co-polymer of ethylene, from 0.1 to 60 wt% of ionomer and grafted polyolefin and from 0 to 60 wt% of functionalised polyolefin, or polyolefin grafted to non-polyolefin in the form of a block copolymer g-NPO), or a mixture thereof; ii) from 0 to 79.9 wt%, based on the weight of external skin layer composition a) of a second metallocene-prepared homo- or co-polymer of ethylene having different density and/or melt index than the first metallocene-prepared homo- or co-polymer of ethylene; a) of a second metallocene-prepared homo- or co-polymer of ethylene having different density and/or melt index than the first metallocene-prepared homo- or co-polymer of ethylene; b) an intermediate foamed polyethylene layer b) prepared from: i) 95 to 99.8 wt% based on the weight of foamed layer b) of a polyethylene composition, the same as or different from that of external skin layer a), said composition comprising a mixture of ionomer and grafted polyolefin, and ii) from 0.2 to 5 wt% of chemical blowing agent, and wherein the mixture of ionomer and grafted polyolefin, blowing agent and metallocene-prepared polyethylene resin have a synergistic effect; i) 95 to 99.8 wt% based on the weight of foamed layer b) of a polyethylene composition, the same as or different from that of external skin layer a), said composition comprising a mixture of ionomer and grafted polyolefin, and ii) from 0.2 to 5 wt% of chemical blowing agent, c) a internal skin layer c), that is a polyethylene-based layer, prepared from a composition consisting of - from 40 to 100 wt%, based on the weight of skin layer c) of a metallocene-prepared homo- or co-polymer of ethylene or a mixture thereof, based on the weight of skin layer b) composition, said polyethylene being the same as or different from that of external skin layer a); - from 0 to 60 wt% of a functionalised polyolefin or of an ionomer or of a polyolefin grafted to a non-polyolefin in the form of a block copolymer g-, or of a mixture thereof; - from 40 to 100 wt%, based on the weight of skin layer c) of a metallocene-prepared homo- or co-polymer of ethylene or a mixture thereof, based on the weight of skin layer b) composition, said polyethylene being the same as or different from that of external skin layer a); - from 0 to 60 wt% of a functionalised polyolefin or of an ionomer or of a polyolefin grafted to a non-polyolefin in the form of a block copolymer g-, or of a mixture thereof; d) optional layers further wherein the multilayer rotomoulded articles are boats.